Question 1

Displacement is which of the following types of quantities?

Accepted Answer

Displacement is a vector quantity as it has both magnitude (distance) and direction.

Question 2

An object moves 20 m east in 30 s and then returns to its starting point taking an additional 50 s.If west is chosen as the positive direction,what is the sign associated with the average velocity of the object?

Accepted Answer

The object returns to its starting point, so the total displacement is zero. Average velocity is displacement divided by time, so the average velocity is zero, which has no sign.

Question 3

Changing the positive direction in a reference frame to the opposite direction does not change the sign of which of the following quantities?

Accepted Answer

C

Question 4

On a position versus time graph,the slope of the straight line joining two points on the plotted curve that are separated in time by the interval Dt,is which of the following quantities?

Accepted Answer

The slope of a position versus time graph represents velocity. When considering two points separated by a time interval Δt, the slope gives the average velocity over that interval.

Question 5

Which of the following is not a vector quantity?

Accepted Answer

Temperature is a scalar quantity, meaning it only has magnitude and not direction. Velocity, acceleration, and displacement are all vector quantities because they have both magnitude and direction.

Question 6

A railroad train travels forward along a straight track at 80.0 m/s for 1 000 m and then travels at 50.0 m/s for the next 1 000 m.What is the average velocity?

Accepted Answer

We can use the formula for average velocity:

average velocity = total displacement / total time

The total displacement is the sum of the two distances traveled:

total displacement = 1000 m + 1000 m = 2000 m

The total time is the sum of the times traveled at each speed:

total time = (1000 m) / (80.0 m/s) + (1000 m) / (50.0 m/s) 
total time = 12.5 s + 20 s = 32.5 s

Plugging in these values, we get:

average velocity = 2000 m / 32.5 s 
average velocity = 61.5 m/s

Therefore, the best choice is B.

Question 7

In one-dimensional motion where the direction is indicated by a plus or minus sign,the average velocity of an object has which of the following properties?

Accepted Answer

The average velocity of an object can be positive, negative or zero depending on the direction of motion. If the object moves in the positive direction, its average velocity is positive. If the object moves in the negative direction, its average velocity is negative. If the object does not move, its average velocity is zero. Therefore, option D is the best choice.

Question 8

A truck moves 70 m east,then moves 120 m west,and finally moves east again a distance of 90 m.If east is chosen as the positive direction,what is the truck's resultant displacement?

Accepted Answer

The truck's resultant displacement is calculated by adding the displacements: 70 m east (positive) + (-120 m west) + 90 m east = 40 m east.

Question 9

A change in a physical quantity w having initial value w_i and final value w_fis given by which of the following?

Accepted Answer

The change in a physical quantity is given by the final value minus the initial value, which is represented by the formula w_f- w_i. Therefore, option B is the correct choice.

Question 10

The distance of the Earth from the sun is 93 000 000 miles.If there are 3.15 ´ 10⁷ s in one year,find the speed of the Earth in its orbit about the sun.

Accepted Answer

The answer of The distance of the Earth from the...

Question 11

An object moves 20 m east in 30 s and then returns to its starting point taking an additional 50 s.If west is chosen as the positive direction,what is the average speed of the object?

Accepted Answer

The answer of An object moves 20 m east in...

Question 12

A bird,accelerating from rest at a constant rate,experiences a displacement of 28 m in 11 s.What is the average velocity?

Accepted Answer

The answer of A bird,accelerating from rest at a constant...

Question 13

A cheetah can run at approximately 100 km/hr and a gazelle at 80.0 km/hr.If both animals are running at full speed,with the gazelle 70.0 m ahead,how long before the cheetah catches its prey?

Accepted Answer

The relative speed of the cheetah with respect to the gazelle is 20 km/hr (100 km/hr - 80 km/hr), which is approximately 5.56 m/s. To cover the 70 m gap at this speed, it takes 70 m / 5.56 m/s = 12.6 seconds.

Question 14

A cheetah can maintain its maximum speed of 100 km/hr for 30.0 seconds.What minimum distance must a gazelle running 80.0 km/hr be ahead of the cheetah to escape?

Accepted Answer

The cheetah can cover 100 km/hr * (30/3600) hr = 0.833 km or 833 m in 30 seconds. The gazelle can cover 80 km/hr * (30/3600) hr = 0.667 km or 667 m in the same time. The minimum distance the gazelle must be ahead is 833 m - 667 m = 166 m, which rounds to 167 m.

Question 15

Consider the magnitude of the average speed,  ,and the magnitude of the average velocity,  ,for the same trip.Which of the following is always true?

Accepted Answer

The answer of Consider the magnitude of the average speed,...

Question 16

A European sports car dealer claims that his car will accelerate at a constant rate from rest to 100 km/hr in 8.00 s.If so,what is the acceleration? (Hint: First convert speed to m/s. )

Accepted Answer

To find the acceleration, first convert 100 km/hr to m/s: 100 km/hr = 100,000 m/3600 s ≈ 27.78 m/s. Using the formula for acceleration, a = (final velocity - initial velocity) / time = (27.78 m/s - 0 m/s) / 8.00 s = 3.47 m/s².

Question 17

A European sports car dealer claims that his product will accelerate at a constant rate from rest to a speed of 100 km/hr in 8.00 s.What is the speed after the first 5.00 s of acceleration? (Hint: First convert the speed to m/s. )

Accepted Answer

The final speed is 100 km/hr, which is approximately 27.78 m/s. The acceleration is constant, so a = (27.78 m/s) / 8 s = 3.4725 m/s². After 5 s, the speed is v = a * t = 3.4725 m/s² * 5 s = 17.3625 m/s, approximately 17.4 m/s.

Question 18

In one-dimensional motion,the average speed of an object that moves from one place to another and then back to its original place has which of the following properties?

Accepted Answer

The average speed of an object in motion is always positive because speed is a scalar quantity that measures the total distance traveled divided by the total time taken, regardless of direction.

Question 19

Jeff throws a ball straight up.For which situation is the vertical velocity zero?

Accepted Answer

The vertical velocity of the ball is zero at the highest point, when it has reached the top of its trajectory and is momentarily at rest before falling back down.

Question 20

A ball is thrown vertically upwards at 19.6 m/s.For its complete trip (up and back down to the starting position),its average velocity is:

Accepted Answer

The average velocity for a complete trip where the starting and ending positions are the same is zero, as displacement is zero.

Quiz 2: Motion in One Dimension

Displacement is which of the following types of quantities?

An object moves 20 m east in 30 s and then returns to its starting point taking an additional 50 s.If west is chosen as the positive direction,what is the sign associated with the average velocity of the object?

Changing the positive direction in a reference frame to the opposite direction does not change the sign of which of the following quantities?

On a position versus time graph,the slope of the straight line joining two points on the plotted curve that are separated in time by the interval Dt,is which of the following quantities?

Which of the following is not a vector quantity?

A railroad train travels forward along a straight track at 80.0 m/s for 1 000 m and then travels at 50.0 m/s for the next 1 000 m.What is the average velocity?

In one-dimensional motion where the direction is indicated by a plus or minus sign,the average velocity of an object has which of the following properties?

A truck moves 70 m east,then moves 120 m west,and finally moves east again a distance of 90 m.If east is chosen as the positive direction,what is the truck's resultant displacement?

A change in a physical quantity w having initial value w_i and final value w_fis given by which of the following?

The distance of the Earth from the sun is 93 000 000 miles.If there are 3.15 ´ 10⁷ s in one year,find the speed of the Earth in its orbit about the sun.

An object moves 20 m east in 30 s and then returns to its starting point taking an additional 50 s.If west is chosen as the positive direction,what is the average speed of the object?

A bird,accelerating from rest at a constant rate,experiences a displacement of 28 m in 11 s.What is the average velocity?

A cheetah can run at approximately 100 km/hr and a gazelle at 80.0 km/hr.If both animals are running at full speed,with the gazelle 70.0 m ahead,how long before the cheetah catches its prey?

A cheetah can maintain its maximum speed of 100 km/hr for 30.0 seconds.What minimum distance must a gazelle running 80.0 km/hr be ahead of the cheetah to escape?

Consider the magnitude of the average speed, ,and the magnitude of the average velocity, ,for the same trip.Which of the following is always true?

A European sports car dealer claims that his car will accelerate at a constant rate from rest to 100 km/hr in 8.00 s.If so,what is the acceleration? (Hint: First convert speed to m/s. )

A European sports car dealer claims that his product will accelerate at a constant rate from rest to a speed of 100 km/hr in 8.00 s.What is the speed after the first 5.00 s of acceleration? (Hint: First convert the speed to m/s. )

In one-dimensional motion,the average speed of an object that moves from one place to another and then back to its original place has which of the following properties?

Jeff throws a ball straight up.For which situation is the vertical velocity zero?

A ball is thrown vertically upwards at 19.6 m/s.For its complete trip (up and back down to the starting position) ,its average velocity is:

Quiz 2: Motion in One Dimension

Displacement is which of the following types of quantities?

An object moves 20 m east in 30 s and then returns to its starting point taking an additional 50 s.If west is chosen as the positive direction,what is the sign associated with the average velocity of the object?

Changing the positive direction in a reference frame to the opposite direction does not change the sign of which of the following quantities?

On a position versus time graph,the slope of the straight line joining two points on the plotted curve that are separated in time by the interval Dt,is which of the following quantities?

Which of the following is not a vector quantity?

A railroad train travels forward along a straight track at 80.0 m/s for 1 000 m and then travels at 50.0 m/s for the next 1 000 m.What is the average velocity?

In one-dimensional motion where the direction is indicated by a plus or minus sign,the average velocity of an object has which of the following properties?

A truck moves 70 m east,then moves 120 m west,and finally moves east again a distance of 90 m.If east is chosen as the positive direction,what is the truck's resultant displacement?

A change in a physical quantity w having initial value wi and final value wf is given by which of the following?

The distance of the Earth from the sun is 93 000 000 miles.If there are 3.15 ´ 107 s in one year,find the speed of the Earth in its orbit about the sun.

An object moves 20 m east in 30 s and then returns to its starting point taking an additional 50 s.If west is chosen as the positive direction,what is the average speed of the object?

A bird,accelerating from rest at a constant rate,experiences a displacement of 28 m in 11 s.What is the average velocity?

A cheetah can run at approximately 100 km/hr and a gazelle at 80.0 km/hr.If both animals are running at full speed,with the gazelle 70.0 m ahead,how long before the cheetah catches its prey?

A cheetah can maintain its maximum speed of 100 km/hr for 30.0 seconds.What minimum distance must a gazelle running 80.0 km/hr be ahead of the cheetah to escape?

Consider the magnitude of the average speed, ,and the magnitude of the average velocity, ,for the same trip.Which of the following is always true?

A European sports car dealer claims that his car will accelerate at a constant rate from rest to 100 km/hr in 8.00 s.If so,what is the acceleration? (Hint: First convert speed to m/s. )

A European sports car dealer claims that his product will accelerate at a constant rate from rest to a speed of 100 km/hr in 8.00 s.What is the speed after the first 5.00 s of acceleration? (Hint: First convert the speed to m/s. )

In one-dimensional motion,the average speed of an object that moves from one place to another and then back to its original place has which of the following properties?

Jeff throws a ball straight up.For which situation is the vertical velocity zero?

A ball is thrown vertically upwards at 19.6 m/s.For its complete trip (up and back down to the starting position) ,its average velocity is:

A change in a physical quantity w having initial value w_i and final value w_fis given by which of the following?

The distance of the Earth from the sun is 93 000 000 miles.If there are 3.15 ´ 10⁷ s in one year,find the speed of the Earth in its orbit about the sun.