Q: A car traveling at $$20 \ \mathrm{m/s}$$ comes to a stop with a constant acceleration of $$-5 \ \mathrm{m/s^2$}. $$What is the stopping distance?

$$s = \dfrac{v^2$}{2a} = \dfrac{(20)^2$}{2 \times 5} = 40 \ \mathrm{m}$$

Q: A ball is dropped from rest and falls freely under gravity. After $$3$$ seconds, what is its velocity?

$$v = g t = 9.8 \times 3 = 29.4 \ \mathrm{m/s}$$

Question 1

A car accelerates from rest at a constant rate of $$2 \ \mathrm{m/s^2$}$$ for $$5$$ seconds. What is its final velocity?

Accepted Answer

$$v_f = 10 \ \mathrm{m/s}$$

Question 2

Which of the following best describes the acceleration vector when an object's velocity is decreasing?

Accepted Answer

The acceleration vector points in the opposite direction to the velocity vector.

Question 3

A ball is dropped from rest from a height $$h in a $$vacuum. Which equation gives the time $$t it $$takes to reach the ground?

Accepted Answer

$$t = \sqrt{\dfrac{2h}{g}}$$

Question 4

If a car's initial speed is doubled, by what factor does its stopping distance increase, assuming constant braking acceleration?

Accepted Answer

The stopping distance increases by a factor of $$4.$$

Question 5

Which kinematic equation is most appropriate for finding the displacement $$\Delta x of an $$object under constant acceleration when initial and final velocities are known?

Accepted Answer

$$\Delta x = \dfrac{v_f + v_i}{2} \Delta t$$

Question 6

A feather and a hammer are dropped simultaneously in a vacuum. What happens?

Accepted Answer

They hit the ground at the same time.

Question 7

An object moves with constant acceleration $$a. If $$its initial velocity is $$v_i$$ and it travels for time $$t$$, what is its displacement?

Accepted Answer

$$\Delta x = v_i t + \dfrac{1}{2} a t^2$

Question 8

A car traveling at $$20 \ \mathrm{m/s}$$ comes to a stop with a constant acceleration of $$-5 \ \mathrm{m/s^2$}. $$What is the stopping distance?

Accepted Answer

$$s = \dfrac{v^2$}{2a} = \dfrac{(20)^2$}{2 	imes 5} = 40 \ \mathrm{m}$$

Question 9

Which of the following statements about acceleration due to gravity near Earth's surface is correct?

Accepted Answer

All objects experience the same acceleration, $$g \approx 9.8 \ \mathrm{m/s^2$}$$, regardless of mass.

Question 10

On a position vs. time graph, what does an upward curvature indicate?

Accepted Answer

A positive acceleration.

Question 11

A ball is thrown straight up with initial velocity $$v_0. $$What is its velocity at the highest point?

Accepted Answer

$$0 \ \mathrm{m/s}$$

Question 12

Which equation can be used to find the final velocity $$v_f of an $$object under constant acceleration if initial velocity $$v_i$$, acceleration $$a$$, and displacement $$\Delta x$$ are known?

Accepted Answer

$$v_f^2$ = v_i^2$ + 2a \Delta x$$

Question 13

A ball is dropped from rest and falls freely under gravity. After $$3$$ seconds, what is its velocity?

Accepted Answer

$$v = g t = 9.8 	imes 3 = 29.4 \ \mathrm{m/s}$$

Question 14

A car is moving to the right and slowing down. What is the direction of its acceleration?

Accepted Answer

To the left (opposite to the direction of motion).

Question 15

Which of the following is NOT a valid kinematic equation for constant acceleration?

Accepted Answer

$$v_f = v_i + \dfrac{1}{2} a t^2$

Question 16

A ball is thrown downward with initial velocity $$v_0$$ from a height $$h. $$Neglecting air resistance, what is the equation for its position after time $$t$$?

Accepted Answer

$$y = h + v_0$ t - \dfrac{1}{2} g t^2$

Question 17

On an inclined plane, which component of gravity causes an object to accelerate down the slope?

Accepted Answer

$$g \sin 	heta$$

Question 18

A car travels with constant acceleration. Which graph best represents its position vs. time?

Accepted Answer

A parabola (quadratic curve).

Question 19

If the acceleration vector and velocity vector of an object point in the same direction, what happens to the object's speed?

Accepted Answer

The object's speed increases.

Kinematics in One Dimension: Acceleration, Gravity, and Motion with Constant Acceleration

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