Conceptual Physics Semester 2 Final Exam Study Guide

Multiple Choice
Identify the choice that best completes the statement or answers the question.

	1.	In order to form an electric circuit, you need to have 
a.	wires or conductors to connect everything.	
b.	a power source.	
c.	a light bulb or some resistance.	
d.	a complete path for the current.	
e.	all of the above	

	2.	In order for there to be a flow of charge from one place to another, there must be a 
a.	conductor, such as a wire, connecting the two places.	
b.	potential difference between the two places.	
c.	Both A and B above	

	3.	An ampere is a 
a.	unit of resistance.	
b.	unit of current.	
c.	type of charge.	
d.	voltage.	
e.	current.	

	4.	Compared to thin wires, electrical resistance in thick wires is 
a.	less.	
b.	the same.	
c.	greater.	

	5.	Current from a battery is always 
a.	DC.	
b.	AC.	

	6.	The law of inertia states that an object 
a.	will continue moving at the same velocity unless an outside force acts on it.	
b.	will continue moving in a straight line unless an outside force acts on it.	
c.	that is not moving will never move unless a force acts on it.	
d.	at rest will remain at rest unless acted on by an outside force.	
e.	will do all of the above.	

	7.	Friction 
a.	comes from microscopic bumps that act as obstructions to the object's motion.	
b.	is the name given to the force acting between surfaces sliding past one another.	
c.	acts in a direction that opposes the motion of an object.	
d.	all of the above	
e.	none of the above	

	8.	One object has twice as much mass as another object. The first object also has twice as much 
a.	velocity.	
b.	gravitational acceleration.	
c.	inertia.	
d.	all of the above	

	9.	Compared to its mass on Earth, the mass of a 10-kg object on the moon is 
a.	the same.	
b.	more.	
c.	less.	

	10.	Which has more mass, a kilogram of feathers or a kilogram of iron?
a.	The feathers	
b.	The iron	
c.	Neither—they both have the same mass.	

	11.	A bag of sports equipment has a mass of 10.0 kilograms and a weight of 
a.	0.98 N.	
b.	9.8 N.	
c.	98 N.	
d.	980 N.	
e.	none of the above	

	12.	Pressure is defined as 
a.	time per area.	
b.	velocity per time.	
c.	force per time.	
d.	force per area.	
e.	distance per time.	

	13.	Which of the following would exert the most pressure on the ground?
a.	A woman standing in running shoes	
b.	A woman standing on skis	
c.	A woman standing in high-heel shoes	

	14.	Suppose a cart is being moved by a force. If suddenly a load is dumped into the cart so that the cart's mass doubles, what happens to the cart's acceleration?
a.	It quarters.	
b.	It halves.	
c.	It stays the same.	
d.	It doubles.	
e.	It quadruples.	

	15.	You are on a frozen pond, and the ice starts to crack. If you lie down on the ice and begin to crawl, this will 
a.	increase the pressure on the ice.	
b.	decrease the pressure on the ice.	
c.	increase the total force on the ice.	
d.	decrease the total force on the ice.	

	16.	How much force is needed to accelerate a 4.0-kg physics book to an acceleration of 2.0 m/s2?
a.	0 N	
b.	2.0 N	
c.	0.5 N	
d.	8.0 N	
e.	24.0 N	

	17.	A jumbo jet cruises at a constant velocity when the total thrust of the engines on the jet is 50,000 N. How much air resistance acts on the jet?
a.	0 N	
b.	25,000 N	
c.	50,000 N	
d.	75,000 N	
e.	100,000 N	

	18.	Forces always occur 
a.	as single quantities.	
b.	by themselves.	
c.	in pairs.	
d.	in triplets.	

	19.	An unfortunate bug splatters against the windshield of a moving car. Compared to the force of the car on the bug, the force of the bug on the car is 
a.	larger.	
b.	the same.	
c.	smaller.	
d.	Need more information to say	

	20.	According to Newton's third law, if you push gently on something, it will push 
a.	gently on something else.	
b.	on you only if you aren't moving.	
c.	gently on you.	
d.	on something only under the right conditions.	

	21.	A woman weighing 550 N sits on the floor. She exerts a force on the floor of 
a.	5.5 N.	
b.	55 N.	
c.	550 N.	
d.	1100 N.	
e.	5500 N.	

	22.	People in the future may well live inside a rotating space structure that is more than 2 km in diameter. Inside the structure, people on the inside of the outer edge will experience 1 g while people halfway to the axis will experience 
a.	2 g.	
b.	1 g.	
c.	 g.	
d.	 g.	
e.	0 g.	

	23.	The resistance an object has to changes in its rotational state of motion is called rotational _____.
a.	inertia	
b.	momentum	
c.	torque	
d.	acceleration	
e.	velocity	

	24.	When an ice skater pulls in his hands to turn faster _____.
a.	angular momentum must be conserved	
b.	his moment of inertia changes	
c.	his rotational speed changes	
d.	all of the above	

	25.	To a person who is inside a spaceship moving close to the speed of light, a meter stick held horizontally inside the ship looks 
a.	squashed in the direction of motion.	
b.	taller.	
c.	wider in the direction of motion.	
d.	shorter.	
e.	just the same as always.	

	26.	To outside observers, objects traveling at relativistic speeds look 
a.	larger.	
b.	smaller.	
c.	the same size.	

	27.	We are actually looking into the past when we look at _____.
a.	starlight	c.	both A and B	
b.	our physics book	d.	none of the above	

	28.	A friend is riding on the back of a truck that is going away from you at 25 km/hr. After the truck passes, your friend throws a ball toward you at 55 km/h relative to her. How fast is the ball going relative to you?
a.	25 km/h	
b.	30 km/h	
c.	55 km/h	
d.	80 km/h	
e.	105 km/h	

	29.	The frequency of a light source doubles as the light approaches you. As the same light source moves away from you at the same speed, its frequency _____.
a.	is doubled	b.	is halved	c.	stays the same	

	30.	As a blinking light source approaches you at an increasing speed, the frequency of the flashes
a.	increases.	b.	stays the same.	c.	decreases.	

	31.	Clocks on a spaceship moving very fast appear to run slow when viewed from _____.
a.	the spaceship	
b.	Earth	
c.	both A and B	
d.	neither A nor B	

	32.	Einstein reasoned that _____.
a.	all motion is relative	
b.	a spaceship cannot measure its speed relative to empty space	
c.	a spaceship can only measure its speed relative to other objects	
d.	all of the above	

	33.	According to the special theory of relativity, all laws of nature are the same in reference frames
a.	that move at constant speeds.	
b.	that accelerate.	
c.	that vibrate.	
d.	that oscillate.	
e.	none of the above	

	34.	Suppose an alien invites you to take a trip on her spaceship. If you travel at the speed of light, you would be
a.	travelling through neither space nor time	
b.	travelling through both space and time	
c.	travelling through time but not through space	
d.	travelling through space but not through time	

	35.	Newton had the insight to see that the _____.
a.	moon is moving	
b.	moon orbits Earth	
c.	force on the moon has the same nature as the force on an apple	
d.	moon always keeps one side toward Earth	
e.	none of the above	

	36.	If the mass of Earth increased, with no change in radius, your weight would _____.
a.	stay the same	
b.	decrease	
c.	increase also	

	37.	A lunar month is about 28 days. If the moon were closer to Earth than it is now, the lunar month would be _____.
a.	more than 28 days	
b.	unchanged at 28 days	
c.	less than 28 days	

	38.	Which is greater, the gravitational force between Earth and the moon, or the force between Earth and the sun?
a.	Earth–moon	
b.	equal	
c.	Earth–sun	

	39.	Why did Newton think there was a force acting on the moon?
a.	Because the moon always keeps one side toward Earth	
b.	Because the moon moves in a curved path	
c.	Because there is no air on the moon	
d.	Because the moon is moving	
e.	all of the above	

	40.	If you were to weigh yourself in an elevator that is in free fall, compared to your ordinary weight, you would weigh _____.
a.	more	
b.	the same	
c.	less, but more than zero	
d.	zero	

	41.	When a star collapses to form a black hole, its mass _____.
a.	decreases	
b.	remains the same	
c.	increases	

	42.	Speed is 
a.	a measure of how fast something is moving.	
b.	always measured in terms of a unit of distance divided by a unit of time.	
c.	the distance covered per unit time.	
d.	all of the above.	
e.	none of the above.	

	43.	In the absence of air resistance, at what other angle will a thrown ball go the same distance as one thrown at an angle of 75 degrees?
a.	15 degrees.	
b.	65 degrees.	
c.	70 degrees.	
d.	80 degrees.	
e.	90 degrees.	

Essay

	44.	What is the difference between direct current and alternating current? When we plug a light bulb into a wall outlet, where do the electrons come from?

	45.	State the law of inertia in its full form and give examples of how it works.

	46.	Write a short paragraph on the difference between mass and weight. Give examples.

	47.	Suppose you are on an airplane moving at high speed. If you flip a coin straight up it will land in your lap rather than a great distance behind you. Explain.

	48.	Suppose you dropped an object into a hole bored completely through the center of Earth to the other side. What would happen to the object? Where is the acceleration the largest? The least? Where is velocity the largest? The least?

	49.	Suppose you are riding on a roller coaster at an amusement park. Discuss how your apparent weight would change as the car accelerates up the track and then coasts back down. What would your apparent weight be if the car were momentarily in free fall?

Problem

	50.	You push with 10.0 N on a 5.0-kg block and there are no opposing forces. How fast will the block accelerate?