: A racing car starts from rest at t = 0 and reachesa final speed v at time t. If the acceleration of the car isconstant during this time, which of the following statementsare true?(a) The car travels a distance vt.(b) The average speed of the car is v/2.(c) The magnitude of the acceleration of the car is v/t.(d) The velocity of the car remains constant.(e) None of statements (a) through (d) is true.Q12: When applying the equations of kinematics for an ob-ject moving in one dimension, which of the following state-ments must be true?(a) The velocity of the object must remain constant.(b) The acceleration of the object must remain constant.(c) The velocity of the object must increase with time.6
Question
: A racing car starts from rest at t = 0 and reachesa final speed v at time t. If the acceleration of the car isconstant during this time, which of the following statementsare true?(a) The car travels a distance vt.(b) The average speed of the car is v/2.(c) The magnitude of the acceleration of the car is v/t.(d) The velocity of the car remains constant.(e) None of statements (a) through (d) is true.Q12: When applying the equations of kinematics for an ob-ject moving in one dimension, which of the following state-ments must be true?(a) The velocity of the object must remain constant.(b) The acceleration of the object must remain constant.(c) The velocity of the object must increase with time.6
Solution 1
Sure, I can do that. Here are the answers to your questions:
For the first question:
(a) False. The car does not travel a distance of vt. The distance traveled by the car is given by the equation (1/2)at^2, where a is acceleration and t is time.
(b) True. The average speed of the car is v/2. This is because the car starts from rest and reaches a final speed of v, so the average speed is (0 + v)/2 = v/2.
(c) True. The magnitude of the acceleration of the car is v/t. This is because acceleration is the change in velocity over time, and the velocity changes from 0 to v over a time period of t.
(d) False. The velocity of the car does not remain constant. It starts from 0 and increases to v.
For the second question:
(a) False. The velocity of the object does not have to remain constant when applying the equations of kinematics.
(b) True. The acceleration of the object must remain constant when applying the equations of kinematics. This is a basic assumption in these equations.
(c) False. The velocity of the object does not have to increase with time. It can also decrease or remain constant.
Solution 2
Sure, I can do that. Here are the answers to your questions:
For the first question:
(a) False. The car does not travel a distance of vt. The distance traveled by the car is given by the equation (1/2)at^2, where a is acceleration and t is time.
(b) True. The average speed of the car is v/2. This is because the car starts from rest and reaches a final speed of v, so the average speed is (0 + v)/2 = v/2.
(c) True. The magnitude of the acceleration of the car is v/t. This is because acceleration is the change in velocity over time, and the velocity changes from 0 to v over a time period of t.
(d) False. The velocity of the car does not remain constant. It starts from 0 and increases to v.
For the second question:
(a) False. The velocity of the object does not have to remain constant when applying the equations of kinematics.
(b) True. The acceleration of the object must remain constant when applying the equations of kinematics. This is a basic assumption in these equations.
(c) False. The velocity of the object does not have to increase with time. It can also decrease or remain constant.
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