Question 1

A baseball is hit upward and travels along a parabolic arc before it strikes the ground. Which one of the following statements is necessarily true?

Accepted Answer

A) The acceleration of the ball decreases as the ball moves upward. 
B) The velocity of the ball is zero m/s when the ball is at the highest point in the arc. 
C) The acceleration of the ball is zero m/s2 when the ball is at the highest point in the arc. 
D) The x-component of the velocity of the ball is the same throughout the ball's flight. 
E) The velocity of the ball is a maximum when the ball is at the highest point in the arc. 
A) The acceleration of the ball decreases as the ball moves upward. 
B) The velocity of the ball is zero m/s when the ball is at the highest point in the arc. 
C) The acceleration of the ball is zero m/s2 when the ball is at the highest point in the arc. 
D) The x-component of the velocity of the ball is the same throughout the ball's flight. 
E) The velocity of the ball is a maximum when the ball is at the highest point in the arc.

Question 2

A ball is fired at an angle of 45°, the angle that yields the maximum range in the absence of air resistance. What is the ratio of the ball's maximum height to its range?

Accepted Answer

A) 1.0 
B) 0.75 
C) 0.67 
D) 0.50 
E) 0.25 
A) 1.0 
B) 0.75 
C) 0.67 
D) 0.50 
E) 0.25

Question 3

A spring-loaded gun is aimed horizontally and is used to launch identical balls with different initial speeds. The gun is at a fixed position above the floor. The balls are fired one at a time.   If the speed of the second ball fired is twice the speed of the first ball fired, how is the horizontal range (denoted R in the figure) affected?

Accepted Answer

A) The range for both balls will be the same. 
B) The range of the second ball will be half as much as that of the first ball. 
C) The range of the second ball will be twice as large as that of the first ball. 
D) The range of the second ball is about 1.4 times larger than that of the first ball. 
E) The range of the second ball will be smaller than that of the first ball by a factor of 1.4. 
A) The range for both balls will be the same. 
B) The range of the second ball will be half as much as that of the first ball. 
C) The range of the second ball will be twice as large as that of the first ball. 
D) The range of the second ball is about 1.4 times larger than that of the first ball. 
E) The range of the second ball will be smaller than that of the first ball by a factor of 1.4.

Question 4

A projectile is fired horizontally with an initial speed of 57 m/s. What are the horizontal and vertical components of its displacement 3.0 s after it is fired? horizontal vertical

Accepted Answer

A) 44 m -29 m 
B) 170 m zero m 
C) 170 m -44 m 
D) 210 m -44 m 
E) 210 m zero m 
A) 44 m -29 m 
B) 170 m zero m 
C) 170 m -44 m 
D) 210 m -44 m 
E) 210 m zero m

Question 5

An eagle is flying due east at 8.9 m/s carrying a gopher in its talons. The gopher manages to break free at a height of 12 m. What is the magnitude of the gopher's velocity as it reaches the ground? Note: effects of air resistance are not included in this calculation.

Accepted Answer

A) 22 m/s 
B) 18 m/s 
C) 11 m/s 
D) 9.8 m/s 
E) 8.9 m/s 
A) 22 m/s 
B) 18 m/s 
C) 11 m/s 
D) 9.8 m/s 
E) 8.9 m/s

Question 6

A boat that can travel at 4.0 km/h in still water crosses a river with a current of 2.0 km/h. At what angle must the boat be pointed upstream (that is, relative to its actual path) to go straight across the river?

Accepted Answer

A) 27° 
B) 30° 
C) 60° 
D) 63° 
E) 90° 
A) 27° 
B) 30° 
C) 60° 
D) 63° 
E) 90°

Question 7

What is the magnitude of the projectile's velocity just before it strikes the ground?

Accepted Answer

A) zero m/s 
B) 9.8 m/s 
C) 30 m/s 
D) 40 m/s 
E) 50 m/s 
A) zero m/s 
B) 9.8 m/s 
C) 30 m/s 
D) 40 m/s 
E) 50 m/s

Question 8

A projectile fired from a gun has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively.
-Approximately how long does it take the projectile to reach the highest point in its trajectory?

Accepted Answer

A) 1 s 
B) 2 s 
C) 4 s 
D) 8 s 
E) 16 s 
A) 1 s 
B) 2 s 
C) 4 s 
D) 8 s 
E) 16 s

A baseball is hit upward and travels along a parabolic arc before it strikes the ground. Which one of the following statements is necessarily true?

A ball is fired at an angle of 45°, the angle that yields the maximum range in the absence of air resistance. What is the ratio of the ball's maximum height to its range?

A projectile is fired horizontally with an initial speed of 57 m/s. What are the horizontal and vertical components of its displacement 3.0 s after it is fired? horizontal vertical

An eagle is flying due east at 8.9 m/s carrying a gopher in its talons. The gopher manages to break free at a height of 12 m. What is the magnitude of the gopher's velocity as it reaches the ground? Note: effects of air resistance are not included in this calculation.

A boat that can travel at 4.0 km/h in still water crosses a river with a current of 2.0 km/h. At what angle must the boat be pointed upstream (that is, relative to its actual path) to go straight across the river?

What is the magnitude of the projectile's velocity just before it strikes the ground?

A projectile fired from a gun has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively. -Approximately how long does it take the projectile to reach the highest point in its trajectory?

Introduction and Mathematical Concepts

Kinematics in One Dimension

Forces and Newtons Laws of Motion

Dynamics of Uniform Circular Motion

Work and Energy

Impulse and Momentum

Rotational Kinematics

Rotational Dynamics

Simple Harmonic Motion and Elasticity

Fluids

Temperature and Heat

The Transfer of Heat

The Ideal Gas Law and Kinetic Theory

Thermodynamics

Waves and Sound

The Principle of Linear Superposition and Interference Phenomena

Electric Forces and Electric Fields

Electric Potential Energy and the Electric Potential

Electric Circuits

Magnetic Forces and Magnetic Fields

Electromagnetic Induction

Alternating Current Circuits

Electromagnetic Waves

The Refl Ection of Light: Mirrors

The Refraction of Light: Lenses and Optical Instruments

Interference and the Wave Nature of Light

Special Relativity

Particles and Waves

The Nature of the Atom

Nuclear Physics and Radioactivity

Ionizing Radiation, Nuclear Energy, and Elementary Particles

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Exam 3: Kinematics in Two Dimensions

A baseball is hit upward and travels along a parabolic arc before it strikes the ground. Which one of the following statements is necessarily true?

A ball is fired at an angle of 45°, the angle that yields the maximum range in the absence of air resistance. What is the ratio of the ball's maximum height to its range?

A projectile is fired horizontally with an initial speed of 57 m/s. What are the horizontal and vertical components of its displacement 3.0 s after it is fired? horizontal vertical

An eagle is flying due east at 8.9 m/s carrying a gopher in its talons. The gopher manages to break free at a height of 12 m. What is the magnitude of the gopher's velocity as it reaches the ground? Note: effects of air resistance are not included in this calculation.

A boat that can travel at 4.0 km/h in still water crosses a river with a current of 2.0 km/h. At what angle must the boat be pointed upstream (that is, relative to its actual path) to go straight across the river?

What is the magnitude of the projectile's velocity just before it strikes the ground?

A projectile fired from a gun has initial horizontal and vertical components of velocity equal to 30 m/s and 40 m/s, respectively. -Approximately how long does it take the projectile to reach the highest point in its trajectory?

Introduction and Mathematical Concepts

Kinematics in One Dimension

Forces and Newtons Laws of Motion

Dynamics of Uniform Circular Motion

Work and Energy

Impulse and Momentum

Rotational Kinematics

Rotational Dynamics

Simple Harmonic Motion and Elasticity

Fluids

Temperature and Heat

The Transfer of Heat

The Ideal Gas Law and Kinetic Theory

Thermodynamics

Waves and Sound

The Principle of Linear Superposition and Interference Phenomena

Electric Forces and Electric Fields

Electric Potential Energy and the Electric Potential

Electric Circuits

Magnetic Forces and Magnetic Fields

Electromagnetic Induction

Alternating Current Circuits

Electromagnetic Waves

The Refl Ection of Light: Mirrors

The Refraction of Light: Lenses and Optical Instruments

Interference and the Wave Nature of Light

Special Relativity

Particles and Waves

The Nature of the Atom

Nuclear Physics and Radioactivity

Ionizing Radiation, Nuclear Energy, and Elementary Particles

Filters