Kinematics Review Assignment

 

 

1.         A ball is thrown in the air. Its initial velocity was 10. m/s. How long will it take to reach its highest point? What height did it reach?

 

2.         You decide to ride your bike. You start from rest and accelerate uniformly at 2.00 m/s2 for 6.0 seconds, then you move with a uniform velocity for 1.0 s, and then you accelerate uniformly at 1.00 m/s2 for 2.0 s. Sketch the velocity time graph. What is your total displacement?

 

                  3.         A jogger runs 6.0 km [E], then 4.0 km [N], and finally 2.0 km [W]. The entire trip takes 2.0 h to complete. Calculate the jogger's

(a)  average speed

(b)  average velocity

 

                  4.         A plane leaves Toronto and flies with an airspeed of 2.20 ´ 102 km/h always pointing due east. A wind is blowing from the north at 8.0 ´ 101 km/h.

(a)  What is the plane's velocity relative to the ground?

(b)  What is the plane's displacement from Toronto after flying for 2.5 h?

 

 

     

 

      5.   In the formula , a) solve for     b) solve for

      6.   Study the position-time graph pictured below and answer the questions that follow.

(a)  What is the object's final displacement?

(b)  What is the object's average velocity during the interval from t = 3.0 s to t = 7.0 s?

(c)  What is the object's velocity during the time its motion is uniform?

(d)  What is the object's average speed during the entire interval?

(e)  What is the object's average velocity during the entire interval?

(f)  What is the object's instantaneous velocity at t = 1.5 s?

(g)  What is the length of time during which the object does not move at all?

 

                  7.   A car is travelling along a highway with a speed of 25 m/s when the driver sees an obstruction 1.80 ´ 102 m directly ahead. It takes the driver 0.80 s to react and begin braking.

(a)  How far does the car travel before it begins to slow down?

(b)  How long will it take the car to stop once the brakes are applied, provided the car stops just before the obstruction?

(c)  What is the value of the acceleration of the car if it just misses hitting the obstruction?  Assume the acceleration is uniform.


 

Review Assignment

 

 

 

                  1. 1.0 s (round to 2 sig. digits)        5.1 m [up]

 

                  2. 74. m  (you can solve by taking the area under the velocity time graph OR by formulas)

 

                  3.         ANS:             

 

(a)  distance ran

average speed

The jogger's average speed is 6.0 km/h.

 

(b)  jogger's displacement

average velocity

The jogger's average velocity is 2.8 km/h [NE].

 

 

                  4.         ANS:             

 

(a)  plane's velocity relative to the ground

The plane's velocity relative to the ground is 2.3 ´ 102 km/h [70º E of S].

 

(b)  plane's displacement from Toronto after 2.5 h

The plane's displacement from Toronto is 5.9 ´ 102 km[70° E of S].

 

 

 

                  5.         ANS:             

 

 

 

                  6.         ANS:             

 

(a)  16 m [N]

(b)  average velocity = slope of line joining endpoints at t = 3.0 s and t = 7.0 s (3.5 m/s [N])

(c)  from t = 3.0 s to t = 4.5 s, velocity = 6.7 m/s [N]

(d) 

(e) 

(f)  instantaneous velocity = slope of tangent at t = 1.5 s (approximately 1.6 m/s [N])

(g)  1.0 s (from t = 6.0 s to t = 7.0 s)

 

 

                  7.         ANS:             

 

(a) 

The car travels 20 m.

(b)  distance to stop: 180 m – 20 m = 160 m

The time required to stop is 13 s.

(c) 

The acceleration is –2.0 m/s2.