Q: A ball is thrown straight up with an initial velocity of $$v_0 = 20$$\ \mathrm{m/s}$$. Neglecting air resistance, what is the maximum height it reaches? (Use g = 9.8$$\ \mathrm{$$m/s^2$$}$$)

$$\frac{v_0$^2}{2g} = \frac{(20)^2$}{2 \times 9.8} = 20.4\ \mathrm{m}$$

Q: A projectile is launched at an angle $$\theta$$ with initial speed $$v_0. $$Which equation gives the horizontal range (neglecting air resistance)?

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

Q: If a vector $$\vec{A}$$ has components $$A_x = 6$$ and $$A_y = 8$$, what is the angle $$\theta it $$makes with the x-axis?

$$\theta = \tan$$^{-1}$$(8/6) = 53.1^\circ$$

Question 1

A car travels 100 meters north in 5 seconds, then 100 meters east in 5 seconds. What is the magnitude of the average velocity for the entire trip?

Accepted Answer

$$\sqrt{8^2$ + 8^2$} = 11.3\ \mathrm{m/s}$$

Question 2

Which of the following best describes acceleration?

Accepted Answer

The rate of change of velocity with respect to time.

Question 3

A ball is thrown straight up with an initial velocity of $$v_0 = 20$$\ \mathrm{m/s}$$. Neglecting air resistance, what is the maximum height it reaches? (Use g = 9.8$$\ \mathrm{$$m/s^2$$}$$)

Accepted Answer

$$\frac{v_0$^2}{2g} = \frac{(20)^2$}{2 	imes 9.8} = 20.4\ \mathrm{m}$$

Question 4

Which of the following is the correct SI unit for acceleration?

Accepted Answer

$$\mathrm{m/s^2$}$$

Question 5

A vector $$\vec{A}$$ has components $$A_x = 3$$ and $$A_y = 4. $$What is the magnitude of $$\vec{A}$$?

Accepted Answer

$$5$$

Question 6

A projectile is launched at an angle $$	heta$$ with initial speed $$v_0. $$Which equation gives the horizontal range (neglecting air resistance)?

Accepted Answer

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

Question 7

A 2 kg object is acted on by a net force of 10 N. What is its acceleration?

Accepted Answer

$$5\ \mathrm{m/s^2$}$$

Question 8

Which of the following statements about free-body diagrams is correct?

Accepted Answer

Each force acting on the object is represented by a vector labeled with its type.

Question 9

A spacecraft of mass $$2000\ \mathrm{kg} is $$moving in deep space at $$500\ \mathrm{m/s} at$$ $$30^\circ$$ above the x-axis. If the pilot engages an engine providing a constant force of $$20\ \mathrm{kN}$$ along the x-axis for $$20\ \mathrm{s}$$, what is the x-component of the spacecraft's displacement during this time?

Accepted Answer

$$\Delta x = v_{ix} t + \frac{1}{2} a_x t^2$ = (500 \cos 30^\circ) 	imes 20 + \frac{1}{2} 	imes 10 	imes 20^2$ = 8660\ \mathrm{m}$$

Question 10

Which equation correctly relates net force and acceleration for a particle of mass $$m$$?

Accepted Answer

$$F_{\mathrm{net}} = m a$$

Question 11

If a vector $$\vec{A}$$ has components $$A_x = 6$$ and $$A_y = 8$$, what is the angle $$	heta it $$makes with the x-axis?

Accepted Answer

$$	heta = 	an$$^{-1}$$(8/6) = 53.1^\circ$$

Question 12

A cyclist increases her velocity from $$5\ \mathrm{m/s} to$$ $$15\ \mathrm{m/s} in$$ $$2\ \mathrm{s}. $$What is her average acceleration?

Accepted Answer

$$a = \frac{15 - 5}{2} = 5\ \mathrm{m/s^2$}$$

Question 13

Which of the following is NOT a vector quantity?

Accepted Answer

Speed

Question 14

A ball is thrown horizontally from a cliff with speed $$v_0. $$Which equation gives the time to hit the ground if the height is $$h$$?

Accepted Answer

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

Question 15

A car moves with constant acceleration. Which equation gives its position as a function of time?

Accepted Answer

$$x = x_i + v_i t + \frac{1}{2} a t^2$

Question 16

A 5 kg box is pulled by a horizontal force of 25 N on a frictionless surface. What is the acceleration of the box?

Accepted Answer

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

Question 17

Which of the following best describes the trajectory of a projectile (neglecting air resistance)?

Accepted Answer

A parabola

Question 18

A car travels at $$30\ \mathrm{m/s}$$ for $$10\ \mathrm{s}$$, then stops in $$5\ \mathrm{s}$$ with constant acceleration. What is the magnitude of the acceleration during stopping?

Accepted Answer

$$a = \frac{30 - 0}{5} = 6\ \mathrm{m/s^2$}$$

Question 19

Which of the following is the correct expression for the average velocity $$v_{avg}$$ over a time interval $$\Delta t$$?

Accepted Answer

$$v_{avg} = \frac{\Delta x}{\Delta t}$$

PHYSICS 1051: Introductory Physics I – Chapters 1–5 Review Notes

Study Guide - Practice Questions

Study Guide - Flashcards