Q: A jet plane is launched from a catapult on an aircraft carrier. If it reaches a speed of $$42\ \mathrm{m/s} at $$the end of the catapult after $$2.0\ \mathrm{s}$$, assuming constant acceleration, what is the distance traveled?

$$\frac{1}{2} \times 42\ \mathrm{m/s} \times 2.0\ \mathrm{s} = 42\ \mathrm{m}$$

Q: When a ball is thrown straight up with no air resistance, what is the acceleration at its highest point?

$$9.8\ \mathrm{m/s^2$}$$\ \text{downward}$$

Q: A baseball is hit straight up into the air with a speed of $$30\ \mathrm{m/s}. $$Estimate the maximum height it reaches. (Ignore air resistance.)

$$h = \frac{v^2$}{2g} = \frac{(30)^2$}{2 \times 9.8} \approx 46\ \mathrm{m}$$

Q: A projectile is launched with an initial velocity of $$40\ \mathrm{m/s} at an $$angle of $$35^\circ$$ above the horizontal. What is the initial vertical component of the velocity?

$$v_{y0} = 40 \times \sin(35^\circ) \approx 22.9\ \mathrm{m/s}$$

Q: A projectile is launched at $$40\ \mathrm{m/s} at$$ $$35^\circ$$ above the horizontal. What is the time to reach the highest point?

$$t = \frac{v_{y0}}{g} = \frac{40 \times \sin(35^\circ)}{9.8} \approx 2.34\ \mathrm{s}$$

Q: A projectile is launched at $$40\ \mathrm{m/s} at$$ $$35^\circ$$ above the horizontal. What is the horizontal range if it lands at the same height it was launched?

$$R = \frac{v_0$^2 \sin(2\theta)}{g} = \frac{(40)^2$ \sin(70^\circ)}{9.8} \approx 150\ \mathrm{m}$$

Question 1

Which of the following does a car's speedometer measure?

Accepted Answer

Speed

Question 2

The slope of a position versus time graph represents which physical quantity?

Accepted Answer

Velocity

Question 3

A bowling ball is released down a lane. Which position-time graph best represents its motion just after it leaves the bowler's hand?

Accepted Answer

Case 2: Increasing slope (curve upward)

Question 4

A jet plane is launched from a catapult on an aircraft carrier. If it reaches a speed of $$42\ \mathrm{m/s} at $$the end of the catapult after $$2.0\ \mathrm{s}$$, assuming constant acceleration, what is the distance traveled?

Accepted Answer

$$\frac{1}{2} 	imes 42\ \mathrm{m/s} 	imes 2.0\ \mathrm{s} = 42\ \mathrm{m}$$

Question 5

When a ball is thrown straight up with no air resistance, what is the acceleration at its highest point?

Accepted Answer

$$9.8\ \mathrm{m/s^2$}$$\ 	ext{downward}$$

Question 6

A baseball is hit straight up into the air with a speed of $$30\ \mathrm{m/s}. $$Estimate the maximum height it reaches. (Ignore air resistance.)

Accepted Answer

$$h = \frac{v^2$}{2g} = \frac{(30)^2$}{2 	imes 9.8} \approx 46\ \mathrm{m}$$

Question 7

Ignoring air resistance, what happens to the horizontal component of a projectile's velocity during its flight?

Accepted Answer

It remains constant

Question 8

A projectile is launched with an initial velocity of $$40\ \mathrm{m/s} at an $$angle of $$35^\circ$$ above the horizontal. What is the initial vertical component of the velocity?

Accepted Answer

$$v_{y0} = 40 	imes \sin(35^\circ) \approx 22.9\ \mathrm{m/s}$$

Question 9

A projectile is launched at $$40\ \mathrm{m/s} at$$ $$35^\circ$$ above the horizontal. What is the time to reach the highest point?

Accepted Answer

$$t = \frac{v_{y0}}{g} = \frac{40 	imes \sin(35^\circ)}{9.8} \approx 2.34\ \mathrm{s}$$

Question 10

A tiger with a speed of $$5.0\ \mathrm{m/s}$$ leaps horizontally from a cliff and lands $$7.5\ \mathrm{m}$$ from the base. How high is the cliff?

Accepted Answer

$$h = \frac{1}{2}gt^2$, where t$$ = \frac{7.5}{5.0} = 1.5\ \mathrm{s}$$, so h$$ = \frac{1}{2} 	imes 9.8 	imes $$(1.5)^2$$ \approx 11\ \mathrm{m}$$

Question 11

A runner finishes a race and stops. Which position-time graph best represents the runner after crossing the finish line?

Accepted Answer

Case 3: Horizontal line

Question 12

If a ball is thrown upward, what is its velocity at the highest point?

Accepted Answer

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

Question 13

A projectile is launched at $$40\ \mathrm{m/s} at$$ $$35^\circ$$ above the horizontal. What is the horizontal range if it lands at the same height it was launched?

Accepted Answer

$$R = \frac{v_0$^2 \sin(2	heta)}{g} = \frac{(40)^2$ \sin(70^\circ)}{9.8} \approx 150\ \mathrm{m}$$

Question 14

Which of the following best describes the acceleration of a ball thrown straight up at its highest point?

Accepted Answer

Downward and equal to $$g$$

Question 15

A ball is thrown upward and returns to the thrower's hand. Neglecting air resistance, how does the time to rise compare to the time to fall?

Accepted Answer

Time to rise equals time to fall

Question 16

A projectile is launched at an angle. Which component of its velocity changes during flight (neglecting air resistance)?

Accepted Answer

Vertical component

Question 17

A ball rolls down a ramp. Which position-time graph best represents its motion?

Accepted Answer

Case 2: Increasing slope (curve upward)

Question 18

A jet plane accelerates from rest to $$42\ \mathrm{m/s} in$$ $$2.0\ \mathrm{s}. $$What is its acceleration?

Accepted Answer

$$a = \frac{v}{t} = \frac{42}{2.0} = 21\ \mathrm{m/s^2$}$$

Kinematics and Projectile Motion: Study Notes and Practice Questions

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