$$\frac{v_0$^2 \sin^2$ \theta}{2g}$$

$$\sqrt{\frac{2 \times 45}{9.8}} \approx 3.03\ \mathrm{s}$$

$$\frac{v_0$^2 \sin 2\theta}{g}$$

$$15 - (9.8 \times 2) = -4.6\ \mathrm{m/s}$$

Question 1

Which of the following best describes a vector quantity?

Accepted Answer

A quantity that has both magnitude and direction.

Question 2

A car moves 60 km east and then 80 km north. What is the magnitude of its displacement?

Accepted Answer

$$\sqrt{60^2$ + 80^2$} = 100 km$$

Question 3

Which equation correctly represents the position of an object under constant acceleration?

Accepted Answer

$$x = x_0$ + v_0$ t + \frac{1}{2} a t^2$

Question 4

A ball is thrown horizontally from a cliff with an initial speed of $$10\ \mathrm{m/s}. $$How far does it travel horizontally in 2 seconds?

Accepted Answer

$$20\ \mathrm{m}$$

Question 5

Which of the following is NOT a scalar quantity?

Accepted Answer

Displacement

Question 6

A projectile is launched at an angle $$	heta$$ with initial speed $$v_0. $$What is the formula for its maximum height?

Accepted Answer

$$\frac{v_0$^2 \sin^2$ 	heta}{2g}$$

Question 7

If a runner accelerates from rest at $$2\ \mathrm{m/s^2$}$$ for 5 seconds, what is their final velocity?

Accepted Answer

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

Question 8

Which of the following best describes the motion of an object in uniform circular motion?

Accepted Answer

The object moves with constant speed but changing velocity.

Question 9

A stone is dropped from a height of $$45\ \mathrm{m}. $$How long does it take to reach the ground? (Assume $$g = 9.8\ \mathrm{m/s^2$})$$

Accepted Answer

$$\sqrt{\frac{2 	imes 45}{9.8}} \approx 3.03\ \mathrm{s}$$

Question 10

Which of the following is the correct formula for the range of a projectile launched at an angle $$	heta$$ with initial speed $$v_0$$?

Accepted Answer

$$\frac{v_0$^2 \sin 2	heta}{g}$$

Question 11

A cyclist travels 3 km north, then 4 km east. What is the magnitude of the displacement?

Accepted Answer

$$\sqrt{3^2$ + 4^2$} = 5 km$$

Question 12

Which of the following statements about acceleration is correct?

Accepted Answer

Acceleration is the rate of change of velocity.

Question 13

A ball is thrown upward with an initial velocity of $$15\ \mathrm{m/s}. $$What is its velocity after 2 seconds? (Assume $$g = 9.8\ \mathrm{m/s^2$})$$

Accepted Answer

$$15 - (9.8 	imes 2) = -4.6\ \mathrm{m/s}$$

Question 14

Which of the following is a correct vector addition method?

Accepted Answer

Tip-to-tail method

Question 15

A car accelerates from $$5\ \mathrm{m/s} to$$ $$25\ \mathrm{m/s} in 4 $$seconds. What is its acceleration?

Accepted Answer

$$\frac{25 - 5}{4} = 5\ \mathrm{m/s^2$}$$

Question 16

Which of the following is true about the horizontal component of velocity in projectile motion (neglecting air resistance)?

Accepted Answer

It remains constant throughout the motion.

Question 17

A person walks 6 km west, then 8 km south. What is the magnitude of their displacement?

Accepted Answer

$$\sqrt{6^2$ + 8^2$} = 10 km$$

Question 18

Which of the following is the correct formula for average velocity?

Accepted Answer

$$\frac{\Delta x}{\Delta t}$$

Question 19

A ball is projected horizontally from a table 1.25 m high. How long does it take to hit the ground? (Assume $$g = 9.8\ \mathrm{m/s^2$})$$

Accepted Answer

$$\sqrt{\frac{2 	imes 1.25}{9.8}} \approx 0.505\ \mathrm{s}$$

Study Guide: Vectors and Motion in Physics

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