# Physics

## For which value of θ is the range of a projectile fired from ground level a maximum? A) 30° above the horizontal B) 45° above the horizontal C) 55° above the horizontal D) 60° above the horizontal E) 90° above the horizontal.For which value of θ is the height of a projectile fired from ground level a maximum? A) 30° above the horizontal B) 45° above the horizontal C) 55° above the horizontal D) 60° above the horizontal E) 90° above the horizontal.If the initial speed of a projectile is doubled. A) Its range will be increased by 1.41. B) Its range will double. C) Its range will be decreased by a factor of two. D) Its range will quadruple. E) Its range will decrease by a factor of four.

For which value of θ is the range of a projectile fired from ground level a maximum?A) 30° above the horizontalB) 45° above the horizontalC) 55° above the horizontalD) 60° above the horizontalE) 90° above the horizontal For which value of θ is the height of a projectile fired from ground level a maximum?A) 30° …

## A rock is thrown upwards at an angle of 40° with respect to the horizontal. As the rock is rising in its trajectory, the horizontal component of its velocity A) increases. B) decreases. C) remains the same. D) is zero. E) Cannot be determined without additional information.A projectile is launched with an initial velocity of 80 m/s at an angle of 30° above the horizontal. Neglecting air resistance, what is horizontal component of the projectile’s acceleration? A) 80 m/s2 B) 40 m/s2 C) 9.8 m/s2 D) 0 m/s2 E) 4.9 m/s2.A boy kicks a football with an initial velocity of 20 m/s at an angle of 25° above the horizontal. The magnitude of the acceleration of the ball while it is in flight is A) 25 m/s2. B) 20 m/s2. C) 9.8 m/s2. D) 8.4 m/s2. E) 0 m/s2.An athlete throws a ball with a velocity of 40 m/s at an angle of 20° above the horizontal. Which of the following statements is true in this case? A) The vertical component of the velocity remains constant. B) The horizontal component of the velocity changes. C) The vertical component of the velocity changes sign after the ball attains its maximum height. D) The horizontal component of the velocity changes sign after the ball attains its maximum height. E) None of the given choices is correct.

A rock is thrown upwards at an angle of 40° with respect to the horizontal. As the rock is rising in its trajectory, the horizontal component of its velocityA) increases.B) decreases.C) remains the same.D) is zero.E) Cannot be determined without additional information. A projectile is launched with an initial velocity of 80 m/s at an …

## For general projectile motion, the vertical component of a projectile’s acceleration A) is zero. B) remains a non-zero constant. C) continuously increases. D) continuously decreases. E) any of the above, depending on position.For a projectile launched horizontally, the vertical component of a projectile’s velocity A) is zero. B) remains a non-zero constant. C) continuously increases. D) continuously decreases. E) any of the above, depending on position.For a projectile launched horizontally, the horizontal component of a projectile’s velocity A) is zero. B) remains a non-zero constant. C) continuously increases. D) continuously decreases. E) any of the above, depending on position.A ball rolls off the edge of a table. The horizontal component of the ball’s velocity remains constant during its entire trajectory because A) the ball is not acted upon by any force. B) the net force acting on the ball is zero. C) the ball is not acted upon by a force in the horizontal direction. D) the ball is not acted upon by a force in the vertical direction. E) None of the other choices is correct.

For general projectile motion, the vertical component of a projectile’s accelerationA) is zero.B) remains a non-zero constant.C) continuously increases.D) continuously decreases.E) any of the above, depending on position. For a projectile launched horizontally, the vertical component of a projectile’s velocityA) is zero.B) remains a non-zero constant.C) continuously increases.D) continuously decreases.E) any of the above, depending …

## If the acceleration of an object is always directed perpendicular to its velocity, then A) the object is speeding up. B) the object is slowing down. C) the object is moving with a constant velocity. D) the object is turning. E) this situation would not be physically possible.You are trying to cross a river that flows due south with a strong current. You start out in your motorboat on the east bank desiring to reach the west bank directly west from your starting point. You should head your motorboat A) due west. B) due north. C) due south. D) in a southwesterly direction. E) in a northwesterly direction.For general projectile motion, the horizontal component of a projectile’s velocity A) is zero. B) remains a non-zero constant. C) continuously increases. D) continuously decreases. E) any of the above, depending on position.For general projectile motion, the horizontal component of a projectile’s acceleration A) is zero. B) remains a non-zero constant. C) continuously increases. D) continuously decreases. E) any of the above, depending on position.

If the acceleration of an object is always directed perpendicular to its velocity, thenA) the object is speeding up.B) the object is slowing down.C) the object is moving with a constant velocity.D) the object is turning.E) this situation would not be physically possible. You are trying to cross a river that flows due south with …

## Under which of the following conditions would a car have a westward acceleration? A) As a car travels eastward with its velocity is increasing. B) As a car travels eastward with its velocity is decreasing. C) As a car travels westward with its velocity is decreasing. D) As a car travels westward with its velocity is constant. E) As a car travels eastward with its velocity is constant.A car travels along eastward with a constant velocity. The magnitude of the acceleration of the car is A) decreasing. B) increasing. C) non-zero constant. D) zero. E) None of the other choices is correct.If the acceleration vector of an object is directed parallel to the velocity vector, then A) the object is speeding up. B) the object is slowing down. C) the object is moving with a constant velocity. D) the object is turning. E) the object is at rest.If the acceleration vector of an object is directed anti-parallel to the velocity vector, then A) the object is speeding up. B) the object is slowing down. C) the object is moving with a constant velocity. D) the object is turning. E) the object is at rest.

Under which of the following conditions would a car have a westward acceleration?A) As a car travels eastward with its velocity is increasing.B) As a car travels eastward with its velocity is decreasing.C) As a car travels westward with its velocity is decreasing.D) As a car travels westward with its velocity is constant.E) As a …

## Two athletes jump straight up. John has twice the initial speed of Harry. Compared to Harry, John stays in the air A) 0.50 times as long. B) 1.41 times as long. C) twice as long. D) three times as long. E) four times as long.Two athletes jump straight up. John has twice the initial speed of Harry. Compared to Harry, John jumps A) 0.50 times as long. B) 1.41 times as long. C) twice as long. D) three times as long. E) four times as long.Two objects are dropped from a bridge, an interval of 1.0 s apart. During the time that both objects continue to fall, their separation A) increases. B) decreases. C) stays constant. D) increases at first, but then stays constant. E) decreases at first, but then stays constant.From the edge of a roof top you toss a green ball upwards with initial velocity v0 and a blue ball downwards with the same initial velocity. When they reach the ground below, A) the green ball will be moving faster than the blue ball. B) the blue ball will be moving faster than the green ball. C) the two balls will have the same speed.

Two athletes jump straight up. John has twice the initial speed of Harry. Compared to Harry, John stays in the airA) 0.50 times as long.B) 1.41 times as long.C) twice as long.D) three times as long.E) four times as long. Two athletes jump straight up. John has twice the initial speed of Harry. Compared to …