Grade 9 Physics Quiz

What is the primary force acting on a projectile after it is launched (ignoring air resistance)?

• Thrust force

• Gravitational force

• Normal force

• Friction force

In a horizontally launched projectile, how do the horizontal and vertical motions relate to each other?

• They are dependent on each other

• They are independent of each other

• The vertical motion determines the horizontal motion

• The horizontal motion determines the vertical motion

Why does a horizontally launched projectile follow a parabolic path?

• Due to air resistance

• Because of wind direction

• Due to the combination of constant horizontal velocity and uniform vertical acceleration

• Because of rotational motion

At what point in a projectile's trajectory is its vertical velocity equal to zero?

• At the starting point

• At the endpoint

• At the apex

• At the midpoint of its horizontal distance

If a ball is launched with an initial vertical velocity of 1.2 m/s upward, what will be its vertical velocity when it returns to the ground? Neglect air resistance

• 0 m/s

• -1.2 m/s

• 1.2 m/s

• 2.4 m/s

Why do horizontally launched projectiles with different initial speeds reach different heights at the same horizontal distance?

• Because of differences in mass

• Due to air resistance

• Because faster projectiles are in the air for less time

• Because slower projectiles have more gravitational pull

What happens to the horizontal velocity vectors of a projectile throughout its flight (ignoring air resistance)?

• They increase in magnitude

• They decrease in magnitude

• They remain constant in magnitude

• They change direction continuously

If a ball is launched at 5.5 m/s at 76° above horizontal, what is its maximum height?

• 2.90 m

• 1.45 m

• 3.20 m

• 0.72 m

How does gravity on the Moon (1/6 of Earth's gravity) affect a projectile's maximum height compared to Earth?

• The maximum height would be the same

• The maximum height would be 1/6 as high

• The maximum height would be 6 times higher

• The maximum height would be 1/3 as high

What is uniform circular motion?

• The movement of an object at varying speeds in a circle

• The movement of an object at a constant speed around a circle with a fixed radius

• The movement of an object in a straight line at constant speed

• The movement of an object in an elliptical path