Question 1

Which of the following statements about experimental measurements and uncertainties is correct?

Accepted Answer

Crude estimates of measurement uncertainties are better than none at all.

Question 2

What is the correct result for $$103.5 - 102.24$$ written with the appropriate number of significant figures?

Accepted Answer

$$1.26$$

Question 3

A car is traveling to the left (negative x-direction) and begins to slow down as it approaches a traffic light. Which statement about its acceleration in the x-direction is correct?

Accepted Answer

Its acceleration is positive but its velocity is negative.

Question 4

A car accelerates from rest to $$v = 20.0\ \mathrm{m/s} at a $$rate of $$3.00\ \mathrm{m/s^2$}. $$How far does the car travel while accelerating?

Accepted Answer

$$133\ \mathrm{m}$$

Question 5

Refer to the velocity-time graph (first image). What is the acceleration of the object at $$t = 2\ \mathrm{s}$$?

Accepted Answer

$$0\ \mathrm{m/s^2$}$$

Question 6

Refer to the velocity-time graph (first image). If the object starts at $$x = 1\ \mathrm{m} at$$ $$t = 0$$, what is its $$x-$$coordinate at $$t = 5\ \mathrm{s}$$?

Accepted Answer

$$0\ \mathrm{m}$$

Question 7

Refer to the acceleration-time graph (second image). If the velocity at $$t = 0 is$$ $$6.0\ \mathrm{m/s}$$, what is the velocity at $$t = 12\ \mathrm{s}$$?

Accepted Answer

$$7.5\ \mathrm{m/s}$$

Question 8

Given $$\vec{A} = 3.00\hat{i} - 2.00\hat{j}$$ and $$\vec{B} = -6.00\hat{i} + 4.00\hat{j} + 1.50\hat{k}$$, what is the magnitude of $$\vec{C} = \vec{A} 	imes \vec{B}$$?

Accepted Answer

$$5.41$$

Question 9

Refer to the vector diagram (third image). If $$|\vec{A}| = 4.00\ \mathrm{m} at$$ $$10.0^\circ$$ from the $$+y-$$axis and $$|\vec{B}| = 7.00\ \mathrm{m} at$$ $$20.0^\circ$$ from the $$+x-$$axis, what is the magnitude and direction of $$\vec{C} = \vec{A} 	imes \vec{B}$$?

Accepted Answer

$$24.2\ \mathrm{m}^2$$, out of the page

Question 10

A basketball is moving in projectile motion. What can you say about the ball’s velocity at the top of its trajectory?

Accepted Answer

The velocity at the top is equal to the x-component of the initial velocity.

Question 11

A box is being pushed up a hill at constant velocity by three people. What is the net force on the box?

Accepted Answer

Zero

Question 12

Refer to the diagram with the box and string (fourth image). A mass $$M = 5.0\ \mathrm{kg} is $$pulled along a rough level surface by a string at $$30^\circ$$ above the horizontal. The tension is $$30\ \mathrm{N}$$ and $$\mu_k = 0.45. $$What is the acceleration of the mass?

Accepted Answer

$$0.9\ \mathrm{m/s^2$}$$

Question 13

Refer to the pulley system (fifth image). Block A weighs $$45\ \mathrm{N}$$ and block B weighs $$25\ \mathrm{N}. $$Block B descends at constant velocity. What is the coefficient of kinetic friction $$\mu_k$$ between block A and the table?

Accepted Answer

$$0.48$$

Question 14

Refer to the inclined plane (sixth image). A box of mass $$M = 2.0\ \mathrm{kg}$$ slides down a $$60^\circ$$ ramp with $$a = 4.6\ \mathrm{m/s^2$}. $$What is the coefficient of sliding friction $$\mu_k$$?

Accepted Answer

$$0.53$$

Question 15

A 60.0-kg person rides in an elevator while standing on a scale. The scale reads 400 N. What is the acceleration of the elevator?

Accepted Answer

$$3.13\ \mathrm{m/s^2$}$$ downward

Question 16

A 600-kg car is going around a curve of radius $$120\ \mathrm{m}$$ banked at $$25.0^\circ. $$The coefficient of static friction is $$0.300. $$What is the magnitude of the force exerted by friction on the car?

Accepted Answer

$$3430\ \mathrm{N}$$

Question 17

A student slides her $$80.0\ \mathrm{kg}$$ desk across the floor for $$4.00\ \mathrm{m} at $$constant speed. If $$\mu_k = 0.400$$, how much work did she do?

Accepted Answer

$$1.26\ \mathrm{kJ}$$

Physics with Calculus: Practice Exam 1 – Step-by-Step Study Guidance

Guida di studio - Domande di pratica

Study guide - Flashcard