Question

1 identify if the following is speed, velocity or acceleration. speed velocity acceleration a car driving on a race track that takes corners at a constant speed a balloon racer traveling 65 cm/s a bird flying 10 m/hr south a biker traveling faster down a hill a skateboard coming to a sudden stop when it hits a rock a box sliding to the left at 5 m/s 6 drag and drop the right answer in the answers below. the forces that are acting on a car going 60 miles per hour, for 3 consecutive hours are, and the car is. the forces acting on a tree branch that is randomly swaying back and forth are, and the branches are. drag & drop the answer unbalanced balanced accelerating not accelerating note: use ctrl+d to drag the option via keyboard 8 if there is no external force on a moving object, it will... (select all that will apply) a stop moving. b keep moving with constant velocity. c gradually slow down until it stops. d gradually speed up. e maintain the same state of motion.

Explanation:

Problem 1 (Identifying Speed, Velocity, Acceleration)

• A car driving on a race track that takes corners at a constant speed: When a car takes corners, its direction changes. Velocity is speed with direction, so a change in direction means a change in velocity, which is acceleration. So this is acceleration.
• A balloon racer traveling 65 cm/s: This gives a magnitude of speed with no direction specified, so it's speed.
• A bird flying 10 m/hr south: This has both magnitude (10 m/hr) and direction (south), so it's velocity.
• A biker traveling faster down a hill: The speed is increasing, so there's a change in velocity (acceleration).
• A skateboard coming to a sudden stop when it hits a rock: The velocity is changing (decreasing to zero), so this is acceleration.
• A box sliding to the left at 5 m/s: This has magnitude (5 m/s) and direction (left), so it's velocity.

• Car going 60 miles per hour for 3 hours: If the car is moving at a constant speed and direction (implied by constant speed for hours), the forces are balanced (e.g., engine force and friction/air resistance balance). A balanced force means no acceleration, so the car is not accelerating.
• Tree branch swaying back and forth: The motion is changing (direction and speed), so the forces are unbalanced. Unbalanced forces cause acceleration, so the branches are accelerating.

Newton's First Law (Law of Inertia) states that an object in motion will stay in motion with constant velocity (same speed and direction) unless acted upon by a net external force.

• Option A: An object stops only if a force (like friction) acts, so without external force, it won't stop. Eliminate A.
• Option B: Matches Newton's First Law. Correct.
• Option C: Slowing down requires a force (friction), so without external force, it won't slow. Eliminate C.
• Option D: Speeding up requires a net force, so without external force, it won't speed up. Eliminate D.
• Option E: "Maintain the same state of motion" means constant velocity (same speed and direction), which matches Newton's First Law. Correct.

Answer:

s:

• a car driving on a race track that takes corners at a constant speed: acceleration
• a balloon racer traveling 65 cm/s: speed
• a bird flying 10 m/hr south: velocity
• a biker traveling faster down a hill: acceleration
• a skateboard coming to a sudden stop when it hits a rock: acceleration
• a box sliding to the left at 5 m/s: velocity

Problem 6 (Forces and Motion State)