speed = distance/time
Answer:
velocity= distance divided by time
How often does a 16-year-old need a medical evaluation from a doctor?
A.
once every 6 months
B.
once every 3 years
C.
once every 1 year
D.
once every 2 years
Please select the best answer from the choices provided.
A
B
C
D
Answer:
b
i just took the quiz
Answer:
The correct answer is B. once every 3 years
1. A student is biking to school. She travels 0.7 km north, then realizes something has fallen out of her bag.
She travels 0.3 km south to retrieve her item. She then travels 0.4 mi north to arrive at school. The journey
takes her 15 min.
a. What is her total displacement?
b. What is her average velocity?
Explanation:
(a) Displacement of an object is the shortest path covered by it.
In this problem, a student is biking to school. She travels 0.7 km north, then realizes something has fallen out of her bag. She travels 0.3 km south to retrieve her item. She then travels 0.4 mi north to arrive at school.
0.4 miles = 0.64 km
displacement = 0.7-0.3+0.64 = 1.04 km
(b) Average velocity = total displacement/total time
t = 15 min = 0.25 hour
[tex]v=\dfrac{1.04\ km}{0.25\ h}\\\\v=4.16\ km/h[/tex]
Hence, this is the required solution.
HELP ANSWER QUESTION 1
Why is the sky blue
A. It's lonely and sad
B. Gases and particles in Earth's atmosphere scatter sunlight in all directions
C. Because it absorbs all colors except blue
Answer:
B
Explanation:
Test
A car accelerates from rest (zero speed) up to a speed of 30m/s in 12
seconds. Calculate the acceleration.
Answer:
Explanation:
v=u+at
30=0+a×12
30=12a
a=[tex]\frac{30}{12}[/tex]
a=2.5ms⁻²
2. A 55 kg woman has a momentum of 200 kg m/s. What is her velocity?
Use: V= p/m to determine the velocity.
Hurry And Help !!!!!
Answer:
[tex]\boxed {\tt 3.63636364 \ m/s}[/tex]
Explanation:
Velocity can be found using the following formula:
[tex]v=\frac{p}{m}[/tex]
where p is the momentum and m is the mass.
The woman has a mass of 55 kilograms and a momentum of 200 kilogram meters per second.
[tex]p= 200 \ kgm/s\\m=55 \ kg[/tex]
Substitute the values into the formula.
[tex]v=\frac{200 \ kg m/s}{55 \ kg}[/tex]
Divide. Note that the kilograms, or kg, will cancel each other out.
[tex]v=\frac{200 \ m/s}{55}[/tex]
[tex]v= 3.63636364 \ m/s[/tex]
The woman's velocity is 3.63636364 meters per second.
Instruments in an airplane which is in level flight indicate that the velocity relative to the air (airspeed) is 180.00 km/h and the direction of the relative velocity vector (heading) is 70° east of north. Instruments on the ground indicate that the velocity of the airplane (ground speed) is 150.00 km/h and the direction of flight (course) is 60° east of north. Determine the wind speed and direction. (Round the final answer to two decimal places.)
Answer:
Explanation:
From the given information:
The coordinate axis is situated in the east and north direction.
So, the north will be the y-axis and the east will be the x-axis
Similarly, the velocity of the plane in regard to the air in the coordinate system will be [tex]v_{P/A} = v( cos \theta \ i + sin \theta \ j)[/tex]
where:
[tex]v_{P/A}[/tex] = velocity of the plane in regard to the air
v = velocity
θ = angle of inclination of the plane with respect to the horizontal
replacing v = 180 km/ and θ = 20° in above equation, then:
The velocity of the airplane in the coordinate system as:
[tex]v_{P} = v_o( cos \phi \ i + sin \phi \ j)[/tex]
where;
[tex]v_p[/tex] = velocity of the airplane
[tex]v_o[/tex] = velocity
∅ = angle of inclination with regard to the base axis;
Then; replacing [tex]v_o[/tex] = 150 km/h and ∅ = 30°
Therefore, the velocity of the plane in the system is :
[tex]v_p = v_A + v_{P/A}[/tex]
[tex]v_A= v_P -v_{P/A}[/tex] --- (1)
[tex]v_A=[/tex] ( 150 cos 30° - 180 cos 20°)i + ( 150 sin 30° - 180sin 20°)j
[tex]v_A=[/tex] (-39.24 km/h)i + (13.44 km/h) j
The magnitude is:
[tex]v_A= (-39.24 km/h)i + (13.44 km/h) j[/tex]
[tex]|v_A|^2 = \sqrt{ (-39.24 km/h)^2+ (13.44 km/h)^2}[/tex]
[tex]v_A[/tex] = 41.48 km/h
The airplane is moving at an angle of the inverse tangent to the abscissa and ordinate.
The angle of motion is:
tan θ = 39.24/13.44
tan θ = 2.9
θ = [tex]tan ^{-1} (2.9)[/tex]
θ = 70.97°
The angle of motion is 70.97° from west of north with a velocity of 41.48 km/h.
How can you turn off a magnetic field produced by an electrical current?
a By placing a material with strong magnetic properties inside the coil of a solenoid b By making a loop or coil in the wire c By increasing the current in the wire d By turning the electrical current off
Answer:By turning the electrical current off
Explanation:Trust me I took the test
Answer:
d) By turning the electrical current off
Explanation:
this is the only one that fits this situation because all of the other answers help improve the magnetic field.
Why is climate changing?
Answer:
because the seasons are changing?
Answer:
Climate is changing because we have seasons.
Explanation:
Do you think it would be possible to get your maximum heart rate ? Why or why not
Answer:
Speaking hypothitically, since I dont have a lot of knowledge around this subject, but yes i think it's possible, and probably not as rare as one might think.
Explanation:
HELPPP!!!
Count the total number of atoms in SiO 2 :
A. 3
B. 4
C. 2
D. 5
E. 6
Answer:3
Explanation:
Answer:
I had this awhile ago if I'm not mistaking its A
BRAINLIEST
20 seconds after launch, a space shuttle would be traveling skyward at a velocity of 139 m/s. What was its average acceleration during the first 20 seconds of the launch? *
A. 0 m/s²
B. 0.14 m/s²
C. 5 m/s²
D. 6.95 m/s²
It took the space shuttle 500 seconds to reach orbital speed of 7823 m/s. What was its average acceleration during this time? *
A. 14.406 m/s²
B. 13.158 m/s²
C. 10.803 m/s²
D. 15.646 m/s²
E. 10.861 m/s²
The space shuttle orbited at a speed of approximately 7823 m/s. How long would it take to travel 100 meters at this speed? *
A. 782, 300s
B. 7723 s
C. 782.3 s
D. 0.013 s
When a space shuttle's boosters were ignited, the shuttle experienced an acceleration of approximately 15 m/s². The launch tower was approximately 60 meters tall. How fast was the shuttle moving when it
Answer:
Explanation:
1) acceleration is the change in velocity of a body with respect to time.
acceleration = velocity/time
Given
velocity = 139m/s
time = 20secs
acceleration = 139/20
acceleration = 6.95m/s²
Hence its average acceleration during the first 20 seconds of the launch is 6.95m/s²
2) Speed is the rate of change of distance with respect to time.
average speed = distance/time
Time = distance/speed
Time = 100/7823
Time = 0.013s
3) Using the equation of motion v² = u²+2as
v² = 0²+2(15)(60)
v² = 30*60
v² =1800
v = √1800
v = 42.43m/s
Do Alkaline Earth Metals occur freely in nature?
Answer:
¨ The alkaline earth elements are metallic elements found in the second group of the periodic table. ... Because of their reactivity, the alkaline metals are not found free in nature.¨
Explanation:
Owing to their electronic configuration and chemical reactivity, alkaline earth metals do not occur freely in nature.
What is electronic configuration?Electronic configuration is defined as the distribution of electrons which are present in an atom or molecule in atomic or molecular orbitals.It describes how each electron moves independently in an orbital.
Knowledge of electronic configuration is necessary for understanding the structure of periodic table.It helps in understanding the chemical properties of elements.
Elements undergo chemical reactions in order to achieve stability. Main group elements obey the octet rule in their electronic configuration while the transition elements follow the 18 electron rule. Noble elements have valence shell complete in ground state and hence are said to be stable.
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iron is electroplated with------ to protect it from corrosion.
a) tin
b). copper
c) silver
d) chromium
Answer:
B) cooper
Explanation:
the Cooper will protect the iro from attack by reagents such as acid
I need help on these 2 questions please ???
Convert 0.0000004372896 to scientific notation.
you can loose your flexibility?
True or false?
Answer:
true
Explanation:
if you stretch a lot and try different/harder things you will become more flexible
A suitcase has a mass of 22.5 kg. This means it weighs
N.
Answer:
The suitcase weighs 225N
Explanation:
Weight can be defined as the force of gravity acting on an object. The unit of the weight of an object is Newton because it is a force.
Given that mass = 22.5
Weight = ?
Weight = mass × acceleration due to gravity.
Acceleration due to gravity = 10m/s2
W = mg
W = 22.5 × 10
W = 225N.
Hence, the suitcase weighs 225N.
A flip is also called ___.
Answer:
A flip is also called a reflection
5. Gravitational and magnetic forces are examples of _______forces.
6_______are forces that are equal in magnitude but opposite in
direction
7.__________are forces that cause a change in the motion of an object.
8. The sum of all forces acting in an object is called________
9. If the forces in an object are balanced, the net force is________
10. If the forces in an object are unbalanced, the net force is________
Answer:
Explanation:
5.non contact force
6.balanced force
7.unbalanced force
8.net force
9.zero
10.is the difference between two forces
mark me as brainliest please
The correct terms for the question are listed below
.non contact force
balanced force
unbalanced force
net force
zero
is the difference between two forces
Gravitational as well as magnetic forces can be regarded as one of the examples of non contact forces.Balance forces can be regarded as a force equal in magnitude and the force I still opposite in direction
Unbalance forces can be regarded as a type of forces that is responsible for alterations in the motion of a particular object.Net force can be regarded as the summation of all forces that is acting in overall on a particular object In a case when a forces in an object are not balanced, then net force is becomes zero
Therefore, Net force give summation of all forces on an object.
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Looking at the examples below and select the change in matter that is an example of a physical change A Ice Melting B leaves changing color C starting a fire
Answer: Your answer will be A
1.Explain frame of reference. How is it different when you are riding inside a car or standing by the highway?
2. Explain Newton’s three laws of motion.
3. When riding in a car that suddenly stops, how is it different when you are wearing a seatbelt or not? Explain how Newton’s laws apply.
4. Define force.
5. Explain balanced and unbalanced force.
6. Describe the four fundamental forces? Arrange them from weakest to strongest.
7. What is work and power and their relationship?
Answer:
See explanation
Explanation:
A frame of reference simply refers to a set of coordinates which is used to determine the position and velocity of objects all the objects found in that particular frame. The person inside the car and standing by the highway are in different frames of reference.
Newtons first law of motion states that an object will continue to be at rest or in a state of uniform velocity until it is acted upon by an external force.
Newtons second law states that rate of change of momentum is directly proportional to the impressed force.
Newtons third law states that action and reaction are equal and opposite.
The action of applying brakes leads to an equal reaction of a sudden forward movement. Seat belts help to prevent the occupants of a car from being injured by the sudden stoppage of the car.
Force is simply defined as a push or pull.
Balanced forces do not lead to acceleration of a body but an unbalanced for leads to acceleration of a body.
strong nuclear force, electromagnetic force, weak nuclear force and gravity
Power is the rate of doing work while week is said to be done when the force applied moves a distance in the direction of the force. Power is defined as work/time.
An oil drop of mass 3.25X10^-15 kg falls vertically with uniform velocity, through the air between vertical parallel plates which are 2 cm apart. When a p.d. of 1000V is applied to the plates ,the drop moves to the positively charged plate, being inclined at 45 degree to the vertical . Calculate the charge on the drop.
Answer:
Explanation:
Do it this way
The charge on the oil drop is 6.37 × 10⁻¹⁹ C
Let F be the resultant force on the charge when it is at 45° to the vertical. The horizontal component of this force, f = Fsin45° and the vertical component of this force f' = Fcos45°.
The vertical component of force equals the weight of the charge, mg.
So, f = mg
Fcos45° = mg (1) where m = mass of oil drop = 3.25 × 10⁻¹⁵ kg and g = acceleration due to gravity = 9.8 m/s²
Also, the horizontal component of the force equals the electric force F' = qE on the charge.
So, f' = qE
Fsin45° = qE (2) where q = charge on oil drop and E = electric field between the plates = V/d where V = potential difference between plates = 1000 V and d = distance between plates = 2 cm = 0.02 m
Dividing equation (2) by (1), we have
Fsin45°/Fcos45° = qE/mg
tan45° = qE/mg
tan45° = qV/dmg
Making q subject of the formula, we have
q = dmgtan45°/V
Substituting the values of the variables into the equation, we have
q = dmgtan45°/V
q = 0.02 m × 3.25 × 10⁻¹⁵ kg × 9.8 m/s² × tan45°/1000 V
q = 0.02 m × 3.25 × 10⁻¹⁵ kg × 9.8 m/s² × 1/1000 V
q = 0.637 × 10⁻¹⁸ C
q = 6.37 × 10⁻¹⁹ C
So, the charge on the oil drop is 6.37 × 10⁻¹⁹ C.
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PLEASE HELP NOW, WILL MARK BRAINLIST!!
The data in the graphs show the progress of a chemical reaction with time by expressing the volume of gas produced in milliliters (ml) over time in minutes. Which graph shows that the chemical reaction eventually stopped?
In this formula, g=GM/R^2 , what do G ,m and R stand for?
Answer:
Explanation:
g means gravitation
G is universal gravitational constant
M = mass of the earth
R = radius of the earth
Hope this helps
plz mark as brainliets!!!!!!!!!
What units are used to measure the magnitude of a vector?
-Grams
-Newtons
-Liters
-Pounds
Answer:
Newtons
Explanation:
Its units are newtons because force has both magnitude and direction.
Do the two cars ever have the same velocity at one instant of time? If so, between which two frames? Check all that apply. Check all that apply. Cars have the same velocity at one instant of time between dots 1 and 2. Cars have the same velocity at one instant of time between dots 2 and 3. Cars have the same velocity at one instant of time between dots 3 and 4. Cars have the same velocity at one instant of time between dots 4 and 5. Cars have the same velocity at one instant of time between dots 5 and 6. Cars never have the same velocity at one instant of time.
Answer:
Cars have the same velocity at one instant of time between dots 4 and 5.
Explanation:
after looking at the image it is visible that same distance is covered by both cars in the frame between 4 and 5
Why is the vertical component of velocity ?
Which of the following procedures demonstrates repetition?
A.
Marco places a toy car at the top of a ramp. He releases the car and measures how long it takes for the car to reach the bottom of the ramp. Then, he returns the car to the top of the ramp, releases the car again, and makes an additional measurement.
B.
Kasey performs a scientific investigation on the effects of using soda instead of water to hydrate plants. Caleb uses Kasey's procedure and performs the same experiment during the following month.
C.
Jeremiah measures the mass of five different strips of metal. He places the strips in five different test tubes filled with hydrochloric acid. He observes if heat and bubbles are produced after the metal strips and acid are combined.
D.
Cynthia monitors the growth rate of her pet turtle. She measures the length and weight of her turtle every Sunday over the course of six months.
Answer: A. Marco places a toy car at the top of a ramp. He releases the car and measures how long it takes for the car to reach the bottom of the ramp. Then, he returns the car to the top of the ramp, releases the car again, and makes an additional measurement
2013 Indianapolis 500 champion Tony Kanaan holds his hand out of his IndyCar while driving through still air with standard atmospheric conditions. (a) For safety, the pit lane speed limit is 60 mph. At this speed, what is the maximum pressure on his hand? (b) Back on the race track, what is the maximum pressure when he is driving his IndyCar at 225 mph? (c) On the straightaways, the IndyCar reaches speeds in excess of 235 mph. For this speed, is your solution method for parts (a and (b) reasonable? Explain.
Answer:
(a). The pressure is 14.76 psi.
(b). The pressure is 15.59 psi.
(c). The pressure is 15.68 psi.
All answer are reasonable.
Explanation:
Given that,
Speed v₁= 60 mph
Speed v₂ = 225 mph
Speed v₃ = 235 mph
(a). We need to calculate the maximum pressure on his hand
Using equation of pressure
[tex]P_{1}=P+\dfrac{1}{2}\rho v^2+\rho gh[/tex]
there, no vertical movement
So, on neglect of height term
[tex]P_{1}=P+\dfrac{1}{2}\rho v_{1}^2[/tex]
Where, P= atmospheric pressure
[tex]\rho[/tex] = air density
v = speed
Put the value in the equation
[tex]P_{1}=14.7\times144+\dfrac{1}{2}\times(0.002376\times(60\times1.4667)^2)[/tex]
[tex]P_{1}=2126.0\ lb/ft^2[/tex]
[tex]P_{1}=\dfrac{2126.0}{144}[/tex]
[tex]P_{1}= 14.76\ psi[/tex]
(b). Speed v₂ = 225 mph
We need to calculate the maximum pressure on his hand
Using equation of pressure
[tex]P_{2}=P+\dfrac{1}{2}\rho v_{2}^2[/tex]
Put the value in the equation
[tex]P_{2}=14.7\times144+\dfrac{1}{2}\times(0.002376\times(225\times1.4667)^2)[/tex]
[tex]P_{2}=2246.17\ lb/ft^2[/tex]
[tex]P_{2}=\dfrac{2246.17}{144}[/tex]
[tex]P_{2}= 15.59\ psi[/tex]
(c). Speed v₃ = 235 mph
We need to calculate the maximum pressure on his hand
Using equation of pressure
[tex]P_{3}=P+\dfrac{1}{2}\rho v_{3}^2[/tex]
Put the value in the equation
[tex]P_{3}=14.7\times144+\dfrac{1}{2}\times(0.002376\times(235\times1.4667)^2)[/tex]
[tex]P_{3}=2257.93\ lb/ft^2[/tex]
[tex]P_{3}=\dfrac{2257.93}{144}[/tex]
[tex]P_{3}= 15.68\ psi[/tex]
According to bernoulli's equation,
If the car increases the velocity the the pressure on the surface of the driver's hand increases.
The pressure from P₁ to P₃ are all near the value of one atmosphere.
So, the pressure difference of one atmosphere is not enough to break the driver's hand.
Hence, (a). The pressure is 14.76 psi.
(b). The pressure is 15.59 psi.
(c). The pressure is 15.68 psi.
All answer are reasonable.
