Physics Units 1 & 2 Concept Quizzes

What is the speed of an object at rest? a 0.0 m/s b 1.0 m/s c 9.8 m/s d 9.81 m/s

a 0.0 m/s

What is the conversion factor between cm^2 and m^2? a 0.0001 m^2/cm^2 b 10000 m^2/cm^2 c 100 m^2/cm^2 d 0.01 m^2/cm^2

a 0.0001 m^2/cm^2

The resultant of two vectors is the smallest when the angle between them is a 180°. b 0°. c 90°. d 45°.

a 180°.

A car travels at 15 m/s for 10 s. It then speeds up with a constant acceleration of 2.0 m/s2 for 15 s. At the end of this time, what is its velocity? a 45 m/s b 15 m/s c 30 m/s d 375 m/s

a 45 m/s

The driver of a car traveling at 110 km/h slams on the brakes so that the car undergoes a constant acceleration, skidding to a complete stop in 4.5 s. If the car skids in a straight line for the entire length of the stopping distance, how long are its skid marks? a 7.0×10^1 m b 1.4×10^2 m c 2.1×10^2 m d 2.5×10^2 m

a 7.0×10^1 m

What is the conversion factor between km/h^2 and m/s^2? a 7.72 × 10^-5 m/s^2 b 1.30 × 10^4 m/s^2 c 2.78 × 10^-1 m/s^2 d 3.60 m/s^2

a 7.72 × 10^-5 m/s^2

Moustapha Jones drives east at 100km/hr for 3 hours then back west at 80km/hr for 1.5 hours. Which pair of answers gives his average speed and average velocity? a 93.3km/hr, 40km/hr east b 40km/hr, 93.3km/hr east c 93.3 km/hr, 40km/hr west d 90km/hr, 40km/hr east

a 93.3km/hr, 40km/hr east

Suppose a ball is thrown downward in the absence of air resistance. Make a statement concerning its acceleration. a Its acceleration is constant. b Its acceleration is constantly increasing. c Its acceleration is constantly decreasing. d Its acceleration is zero.

a Its acceleration is constant.

When a car's velocity is positive and its acceleration is negative, what is happening to the car's motion? a The car slows down. b The car speeds up. c The car travels at constant speed. d The car remains at rest.

a The car slows down.

A brick is dropped from the top of a building. A second brick is thrown straight down from the same building. They are released at the same time. Neglect air resistance. Compare the accelerations of the two bricks. a The two bricks accelerate at the same rate. b The first brick accelerates faster. c The second brick accelerates faster. d It is impossible to determine from the information given.

a The two bricks accelerate at the same rate.

Two objects are thrown from the top of a tall building. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the street? a They are traveling at the same speed. b The one thrown up is traveling faster. c The one thrown down is traveling faster. d It is impossible to tell because the height of the building is not given.

a They are traveling at the same speed.

In a coordinate system, a vector is oriented at angle θ with respect to the x-axis. The x component of the vector equals the vector's magnitude multiplied by which trigonometric function? a cos θ b cot θ c sin θ d tan θ

a cos θ

The metric prefix for one thousand is a kilo. b mega. c centi. d milli.

a kilo.

Which of the following is an example of a vector quantity? a velocity b temperature c volume d mass

a velocity

Calculate the following, and express the answer in scientific notation with the correct number of significant figures: (0.82 + 0.042)(4.4 x 10^3) a 3.8 x 10^3 b 3.78 x 10^3 c 3.784 x 10^3 d 3784

a) 3.8 x 10^3

Which formula is equivalent to D=m/V ? a) V = m/D b) V = Dm c) V = mD/V d) V = D/m

a) V = m/D

Which of the following is the equation for average velocity? a) v_avg = change in x/change in t b) v_avg = change in t/change in x c) v_avg = (change in x)(change in t) d) v_avg = (v_i - v_f) / 2

a) v_avg = change in x/change in t

Vector A has magnitude 8.0 m at an angle of 30 degrees below the +x axis. The y-component of A is a 4.0 m. b -4.0 m. c -6.9 m. d 6.9 m.

b -4.0 m.

John goes for a run. From his house, he jogs north for exactly 5.0 min at an average speed of 8.0 km/h. He continues north at a speed of 12.0 km/h for the next 30.0 min. He then turns around and jogs south at a speed of 15.0 km/h for 15.0 min. Then he jogs south for another 20.0 min at 8.0 km/h. He walks the rest of the way home. How far will John have to walk to get home after he finishes jogging? a 0.0 km b 0.25 km c 5.58 km d 15.0 km

b 0.25 km

For the voltmeter in the image below, what is the reading given by needle A expressed to the best precision of the instrument? a 103mV b 107mV c 110mV d 100.17mV

b 107mV

Estimate the order of magnitude of the length of a football field. a 10^-1 m b 10^2 m c 10^4 m d 10^6 m

b 10^2 m

The sun is composed mostly of hydrogen. The mass of the sun is 2.0x10^30 kg, and the mass of a hydrogen atom is 1.67x10^27 kg. Estimate the number of atoms in the sun. a 10^3 b 10^57 c 10^30 d 10^75

b 10^57

The components of vector A are given as follows: Ax = +3.9 Ay = -4 The angle measured counterclockwise from the x-axis to vector A, in degrees, is closest to: a 136 b 314 c 134 d 224 e 46

b 314

A ball is thrown vertically upward with a speed v. An identical second ball is thrown upward with a speed 2v (twice as fast). What is the ratio of the maximum height of the second ball to that of the first ball? (How many times higher does the second ball go than the first ball?) a 1.4:1 b 4:1 c 1.7:1 d 2:1

b 4:1

The radius of Earth is 6 370 000 m. Express this measurement in km in scientific notation with the correct number of significant digits. a 6.37 x 10^6 km b 6.37 x 10^3 km c 637 x 10^3 km d 63.7x 10^4 km

b 6.37 x 10^3 km

Which of the following is an accurate statement? a The magnitude of a vector can be less than the magnitude of one of its components. b A vector cannot have zero magnitude if one of its components is not zero. c If the magnitude of vector A is less than the magnitude of vector B, then the x-component of A is less than the x-component of B. d The magnitude of a vector can be positive or negative.

b A vector cannot have zero magnitude if one of its components is not zero.

When an object is released from rest and falls in the absence of friction, which of the following is true concerning its motion? a Both its acceleration and its velocity are constant. b Its acceleration is constant. c Neither its acceleration nor its velocity is constant. d Its velocity is constant.

b Its acceleration is constant.

A baseball catcher throws a ball vertically upward and catches it in the same spot as it returns to the mitt. At what point in the ball's path does it experience zero velocity and nonzero acceleration at the same time? a midway on the way up b at the top of its path c the instant it leaves the catcher's hand d the instant before it arrives in the catcher's mitt

b at the top of its path

Two displacement vectors have magnitudes of 5.0 m and 7.0 m, respectively. When these two vectors are added, the magnitude of the sum a is 12 m. b could be as small as 2.0 m, or as large as 12 m. c is larger than 12 m. d is 2.0 m.

b could be as small as 2.0 m, or as large as 12 m.

Moustapha Jones has a problem to do involving time, distance and velocity, but he has forgotten the formula. The question asks him for a measurement in seconds, and the numbers that are given have units of m/s and km. What could Moustapha do to get the answer in seconds? a multiply the km by the m/s then multiply by 1000 b divide the km by the m/s then multiply by 1000 c divide the km by the m/s then divide by 1000 d multiply the km by the m/s then divide by 1000

b divide the km by the m/s then multiply by 1000

The metric prefix for one one-thousandth is a mega. b milli. c centi. d kilo.

b milli

The symbol mm represents a a micrometer. b millimeter. c megameter. d manometer.

b millimeter.

Ball A is dropped from the top of a building. One second later, ball B is dropped from the same building. As time progresses, the difference in their speeds a decreases. b remains constant. c increases. d cannot be determined from the information given.

b remains constant.

Which of the following is a physical quantity that has a magnitude but no direction? a vector b scalar c resultant d frame of reference

b scalar

Identify the following quantities as scalar or vector: the mass of an object, the number of leaves on a tree, wind velocity. a vector, scalar, scalar b scalar, scalar, vector c scalar, vector, scalar d vector, scalar, vector

b scalar, scalar, vector

The number of significant figures in 0.040 is a three. b two. c four. d one.

b two

On a number line graph numbered 0 to 10, a toy car rolls from +3 m to +5 m. Which of the following statements is true? a x_f = +3 m b x_i = +3 m c change in x = +3 m d v_avg = 3 m/s

b x_i = +3 m

If you run a complete loop around an outdoor track (400 m), in 100 s, your average velocity is a 40,000 m/s. b zero. c 0.25 m/s. d 4.0 m/s.

b zero.

Which of the following is the equation for acceleration? a) a = change in t/change in v b) a = change in v/change in t c) a = (change in v)(change in t) d) (v_i − v_f) / (t_i − t_f)

b) a = change in v/change in t

Which of the following has three significant figures? a 1.00081 kg b 8.060 × 10^11 m^2 c 0.0500 mm d 305.0 cm

c 0.0500 mm

John goes for a run. From his house, he jogs north for exactly 5.0 min at an average speed of 8.0 km/h. He continues north at a speed of 12.0 km/h for the next 30.0 min. He then turns around and jogs south at a speed of 15.0 km/h for 15.0 min. Then he jogs south for another 20.0 min at 8.0 km/h. He walks the rest of the way home. How many kilometers does John jog in total? a 3.4 km b 12.5 km c 13.1 km d 785 km

c 13.1 km

Vector A has length 4 units and directed to the north. Vector B has length 9 units and is directed to the south. Calculate the magnitude and direction of A + B. a 13 units, north b 13 units, south c 5 units, south d 5 units, north

c 5 units, south

The driver of a car traveling at 110 km/h slams on the brakes so that the car undergoes a constant acceleration, skidding to a complete stop in 4.5 s. What is the average acceleration of the car during braking? a 24.4 m/s^2 b 13.6 m/s^2 c 6.79 m/s^2 d 138 m/s^2

c 6.79 m/s^2

For the winter, a duck flies 10.0 m/s due south against a gust of wind with a speed of 2.5 m/s. What is the resultant velocity of the duck? a 12.5 m/s south b -12.5 m/s south c 7.5 m/s south d -7.5 m/s south

c 7.5 m/s south

A ball is thrown straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is coming down. a Its velocity points upward and its acceleration points downward. b Both its velocity and its acceleration point upward. c Both its velocity and its acceleration point downward. d Its velocity points downward and its acceleration points upward.

c Both its velocity and its acceleration point downward.

Suppose a ball is thrown straight up. Make a statement about the velocity and the acceleration when the ball reaches the highest point. a Both its velocity and its acceleration are zero. b Its velocity is not zero and its acceleration is zero. c Its velocity is zero and its acceleration is not zero. d Neither its velocity nor its acceleration is zero.

c Its velocity is zero and its acceleration is not zero.

Which would hit the ground first if dropped from the same height in a vacuum—a feather or a metal bolt? a the feather b the metal bolt c They would hit the ground at the same time. d They would be suspended in a vacuum.

c They would hit the ground at the same time.

Which of the following is a pair of vector quantities? a Speed — Distance b Velocity — Distance c Velocity — Displacement d Speed — Displacement

c Velocity — Displacement

The metric prefix for one one-hundredth is a milli. b mega. c centi. d kilo.

c centi

Suppose a ball is thrown straight up. What is its acceleration just before it reaches its highest point? a slightly less than g b slightly greater than g c exactly g d zero

c exactly g

The number of significant figures in 0.01500 is a five. b two. c four. d three.

c four.

Acceleration due to gravity is also called a negative velocity. b displacement. c free-fall acceleration. d instantaneous acceleration.

c free-fall acceleration.

Ball A is dropped from the top of a building. One second later, ball B is dropped from the same building. As time progresses, the distance between them a decreases. b remains constant. c increases. d cannot be determined from the information given.

c increases.

Suppose you are given a position versus time graph. The slope of a line drawn tangent to a point on the curve of this graph describes what quantity? a acceleration b displacement c instantaneous velocity d position

c instantaneous velocity

The SI base unit used to measure mass is the a meter. b second. c kilogram. d liter.

c kilogram.

What is the SI unit of acceleration? a m/s b m^2/s c m/s^2 d m•s^2

c m/s^2

Which of the following units is the SI unit of velocity? a meter b meter•second c meter per second d second per meter

c meter per second

The most appropriate metric unit for measuring the length of an automobile is the a micron. b kilometer. c meter. d nanometer.

c meter.

On a number line graph numbered 0 to 10, what is the correct description of any location to the left of the zero? a negative displacement b negative distance c negative position d negative change of displacement

c negative position

What is the conversion factor between km/h and m/s? a 16.7 m/s b 0.0278 m/s c 3.60 m/s d 0.278 m/s

d 0.278 m/s

The SI base unit for time is a 1 day. b 1 hour. c 1 minute. d 1 second.

d 1 second.

A car is moving with a uniform speed of 15.0 m/s along a straight path. What is the distance covered by the car in 12.0 minutes? a 1.02 × 10^-3 km b 1.80 × 10^-1 km c 8.00 × 10^-5 km d 1.08 × 10^1 km

d 1.08 × 10^1 km

A rectangular garden measures 15 m long and 13.7 m wide. What is the length of a diagonal from one corner of the garden to the other? a 19 m b 4.1 × 10^2 m c 18 m d 20 m

d 20 m

The product of 7.250cm × 6.5cm, given to the correct number of significant digits, is a 47.125cm2 b 47.13cm2 c 47.1cm2 d 47cm2

d 47cm2

The measurement 64.010cm has how many significant digits? a 2 b 3 c 4 d 5

d 5

A motorist travels for 3.0 h at 80 km/h and 2.0 h at 100 km/h. What is her average speed for the trip? a 90 km/h b 85 km/h c 92 km/h d 88 km/h

d 88 km/h

Which of the following situations represents a negative displacement? (Assume positive position is measured vertically upward along a y-axis.) a A cat stands on a tree limb. b A cat jumps from the ground onto a tree limb. c A cat jumps from a lower tree limb to a higher one. d A cat jumps from a tree limb to the ground.

d A cat jumps from a tree limb to the ground.

Which of the following statements applies to the motion of a ball rising and then falling in free fall? I. The ball has constant acceleration as it moves upward. II. The ball has constant acceleration at the top of its path. III. The ball has constant acceleration as it moves downward. a I only b III only c I and III d I, II, and III

d I, II, and III

Suppose a ball is thrown straight up, reaches a maximum height, then falls to its initial height. Make a statement about the direction of the velocity and acceleration as the ball is going up. a Its velocity points downward and its acceleration points upward. b Both its velocity and its acceleration points downward. c Both its velocity and its acceleration point upward. d Its velocity points upward and its acceleration points downward.

d Its velocity points upward and its acceleration points downward.

If you know the acceleration of a car, its initial velocity, and the time interval, which of the following can you predict? a the direction of the car's final velocity b the magnitude of the car's final velocity c the displacement of the car d all of the above

d all of the above

Acceleration is defined as a a rate of displacement. b the rate of change of displacement. c the change in velocity. d the rate of change of velocity.

d the rate of change of velocity.

The components of vector A are given as follows: Ax = +2.4 Ay = -3.1 The magnitude of A is closest to: a 4.7 b 4.3 c 3.1 d 3.5 e 3.9

e 3.9