# SPH3U h1+, Physics, 11, University

1. If an electron travels at a uniform velocity of 105 m/s [N 45° W], how much time is required for a displacement of 10 m in the same direction?

2. A driver wanted to test the braking system of his car. He traveled at 30 m/s, and after applying the brakes, came to a stop in 3.5 s. Calculate the car's acceleration and the distance necessary to the car to stop.

3. A truck is traveling at 108 km/h. Because of an accident on the road, it has to come to a stop. If the truck can decelerate at a constant 4.5 m/s2, how far does it travel before it stops?

4. A car is traveling along a straight road at a constant velocity of 20 m/s. The driver depresses the accelerator, and the velocity of the car changes to 35 m/s in the next ten seconds. Calculate the acceleration of the car.

5. It was once recorded that a Jaguar left skid marks which were 290 m in length. Assuming that the Jaguar skidded to a stop with a constant acceleration of -3.90 m/s2, determine the speed of the Jaguar before it began to skid.

6. A dragster accelerates to a speed of 112 m/s over a distance of 398 m. Determine the acceleration (assume uniform) of the dragster.

7. Calculate the ground velocity of a small motor boat that can travel at 2 m/s in still water but is heading East in a river that has a current of 0.50 m/s [S].

8. An object is pushed from rest across a sheet of ice, accelerating at 5.0 m/s2 over a distance of 80.0 cm. The object then slides with a constant speed for 4.0 s until it reaches a rough section which causes it to stop in 2.5 s. (6 marks)

a. What is the speed of the object when it reaches the rough section?b. At what rate does the object slow down once it reaches the rough section?

c. What total distance does the object slide throughout its entire trip?

9. A dog's position is recorded in the graph below. Determine the velocity of the dog in all three segments. Sketch the corresponding Velocity-Time Graph. (9 marks)

A graph of distance (metres) versus time (seconds). Line segment A demonstrates that the object increases its velocity by 20 metres in the first 10 seconds of its motion. Line segment B demonstrates the velocity remains constant at 20 metres per second for the next 10 seconds. Line segment C demonstrates that the object decreases its velocity by 20 metres in the last 10 seconds of its motion.

10. A sports car's velocity is shown in the graph below. (8 marks)

a. How fast is it traveling at the 5 s mark?

b. What is the acceleration at the 5 s mark?

c. Estimate the acceleration at the 15 s mark. Show your work.

d. During which intervals of time, did the car have a negative acceleration?

11. Using the acceleration-time graph below, sketch the corresponding velocity- time graph. Show your work. (6 marks)

12. When an object falls, the force of gravity causes it to accelerate at 9.8 m/s2 [downward]. Although air resistance can reduce the acceleration, many objects can reach very high speeds when falling toward the Earth. In this assessment, you will investigate a situation that involves acceleration of an object due to gravity.

If the hammer from the previous question was tossed downward at 4.6 m/s from a height of 9.5 m above ground level, how high would it be after 0.75 s?

13. A marble rolls off a desk that is 0.86 m above the floor with a horizontal speed of 1.2 m/s.

a. What is the marble's horizontal velocity when it is half-way to the floor?

b. What is the marble's vertical velocity at that point?

c. Describe the value of the vertical component of velocity as the marble falls to the floor.