Projectile Motion

An object slides off a roof 10 meters above the ground with an initial horizontal speed of 5 meters per second as shown above. The time between the object's leaving the roof and hitting the ground is most nearly

• 0.5 s

• 0.71 s

• 1.4 s

• 2 s

• 7 s

A ball is thrown and follows a parabolic path, as shown above. Air friction is negligible. Point Q is the highest point on the path. Which of the following best indicates the direction of the acceleration, if any, of the ball at point P ?

• To the right

• Down and to the right

• Down

• Left

• There is no acceleration

Which statement regarding points P and Q must be true?

• The projectile is faster at point Q than at point P

• The projectile is faster at point P than at point Q

• The projectile has the same speed at point P and point Q

• The direction of the velocity of the projectile at point P is the same as the direction of the velocity of the projectile at point Q

• None of the above

A soccer ball is kicked with an initial velocity of 10 m/s at an angle of 15 degrees above the horizontal. What is the horizontal distance traveled by the soccer ball?

• 5 m

• 7.071 m

• 8.7 m

• 10 m

• 12.1 m

A projectile is fired from the surface of the Earth with a speed of 200 meters per second at an angle of 30° above the horizontal. If the ground is level, what is the amount of time the projectile is in the air for?

• 5 s

• 10 s

• 15 s

• 20 s

• 25 s

The velocity of a projectile at launch has a horizontal component v_h and a vertical component v_y. Air resistance is negligible. When the projectile is at the highest point of its trajectory, which of the following show the vertical and horizontal components of its velocity and the vertical component of its acceleration?

• vertical velocity =v_y horizontal velocity= v_h

  vertical acceleration= 0

• vertical velocity =v_y horizontal velocity= 0

  vertical acceleration= 0

• vertical velocity = 0 horizontal velocity= v_h

  vertical acceleration= 0

• vertical velocity = 0 horizontal velocity= 0

  vertical acceleration= g

• vertical velocity = 0 horizontal velocity= v_h

  vertical acceleration= g

A projectile is fired horizontally at a speed of 10 m/s. If the projectile takes 3s to hit the ground, with what speed does it strike the ground?

• 0 m/s

• 10 m/s

• 24 m/s

• 32 m/s

• 38 m/s

A spring loaded gun can fire a projectile to a height h if it is fired straight up. If the same gun is pointed at an angle of 45° from the vertical, what maximum height can now be reached by the projectile?

• h/4

• h/2.8

• h/2

• h/1.4

• h

A soccer ball is kicked with an initial velocity of 20 m/s at an angle of 30 degrees. The maximum height reached by the ball is

• 10 m

• 1 m

• 5 m

• 15 m

• 20 m

A projectile is fired horizontally from a height of 20 meters, with an initial velocity of 7 m/s. How far does the projectile fire horizontally before it reaches the ground?

• 7 m

• 14 m

• 140 m

• 3.5 m

• 20 m