Displacement Velocity And Acceleration
A delivery drone flies 500 m north, then 200 m south, and finally 100 m north. Taking north as positive, determine the displacement of the drone from its starting position.
A jogger runs 600 m east and then 600 m west, returning to her starting point. The entire trip takes 200 s. Calculate her average speed and her average velocity.
A train travels 54 km south in 0.75 hours, then 18 km north in 0.25 hours. Taking south as positive, calculate the average velocity of the train for the entire journey in m/s.
A skateboarder moving at +8.0 m/s reaches a downhill slope and accelerates to +14.0 m/s over 3.0 s. Calculate the average acceleration of the skateboarder during this interval.
An object has a velocity of −12.0 m/s and an acceleration of +4.0 m/s². Determine whether the object is speeding up or slowing down, and state the object’s velocity after 2.0 s.
The object model in physics treats a real object as a point particle. Which property is discarded when applying this model?
A car drives 240 m east in 12 s. It then immediately reverses and drives 80 m west in 8 s. Taking east as positive, calculate the car’s average velocity and average speed for the entire trip.
A spacecraft in orbit moves at a constant speed of 7 700 m/s while continuously changing direction around Earth. A student claims the spacecraft has zero acceleration because its speed is constant. Evaluate this claim.
An object starts at position x = −4 m and moves to position x = +9 m. Calculate the displacement.
A position-time graph shows a curved (concave-up) line. A student draws a straight line connecting the position at t = 0 s to the position at t = 10 s and calculates its slope. What quantity has the student determined?
A car initially moving at +25.0 m/s brakes uniformly and comes to rest in 5.0 s. Determine the average acceleration and the displacement during braking using the average velocity method.
A student reads that an object has a negative acceleration and concludes the object must be slowing down. Under what condition is this conclusion incorrect?
A hockey puck slides across ice at +6.0 m/s and experiences a constant friction deceleration. After 4.0 s the puck’s velocity is +2.0 m/s. Calculate the average acceleration and determine how much additional time is needed for the puck to come to rest.
Two identical balls are thrown simultaneously. Ball X is thrown 30 m to the right and returns 30 m to the left, taking 10 s total. Ball Y is thrown 40 m to the right and stays there, also taking 10 s. Which ball has the greater average speed, and which has the greater magnitude of average velocity?
A velocity-time graph shows a straight line that starts at v = +10 m/s at t = 0 s and crosses through v = 0 m/s at t = 5 s, continuing to v = −10 m/s at t = 10 s. Determine the average acceleration between t = 0 s and t = 10 s, and state whether the object is speeding up or slowing down at t = 8 s.
A train departs Station A heading east at t = 0 and arrives at Station B, 9 000 m to the east, at t = 300 s. During the trip the train briefly stopped for 30 s at a signal. Determine the average velocity for the entire journey and explain why the average velocity provides no information about the stop.