1. 10 m/s @ 70°, 10 m/s @ 55°, 10 m/s @ 40°, 10 m/s @ 25°
2. A bowling ball moves without acceleration when it rolls along a bowling alley because the net force acting on it is zero. The force of friction is balanced by the force propelling it forward (initially from the throw), and once rolling steadily, no unbalanced horizontal force acts on it to change its velocity.
3. In the absence of air resistance, the horizontal component of velocity for a projectile remains constant because there is no horizontal force acting on the object. According to Newton’s First Law, an object in motion stays in motion with the same speed and direction unless acted upon by an unbalanced force. The vertical component changes due to the constant downward force of gravity.
4. The downward component of projectile motion is identical to free fall motion. Both involve constant acceleration due to gravity (approximately 9.8 m/s² downward) and start with an initial vertical velocity that may be zero or non-zero depending on launch angle. The equations of motion for the vertical direction are the same as those for free fall.
5.
a. vertical component — accelerated motion with constant acceleration due to gravity
b. horizontal component — uniform motion with constant velocity
6.
a. Time to reach ground: t = √(2h/g) = √(2 × 2.2 / 9.8) ≈ 0.67 seconds
b. Horizontal distance: d = v_x × t = 65 × 0.67 ≈ 43.55 meters
7.
a. Time to reach ground: t = √(2h/g) = √(2 × 1.3 / 9.8) ≈ 0.515 seconds
b. Horizontal distance: d = v_x × t = 950 × 0.515 ≈ 489.25 meters
Parent Tip: Review the logic above to help your child master the concept of projectile motion problems worksheet.
