1.Three forces, each of 36 lb, act on the same object.

What is

the maximum total force they can exert on the object?

The minimum

total force? F_max=

lb; F_min=

lb

2.A car whose acceleration is constant reaches a speed of79 km/hin15 sstarting from rest.How muchmore time is required for it to reach a speed of117 km/h? Round to one decimal place.

3.The brakes of a car are applied to give it an acceleration of 4 m/s².The carcomes to a stop in5 s.What wasits speed when the brakes were applied?

4.A car starts from rest and reaches a speed of25.0 m/sin6.0 s.If itsacceleration remains the same, how fast will it be moving6 slater?Round yourintermediate step to three decimal places and the final answer to the nearest integer.

5.The brakes of a car moving at6 m/sare applied, and the car comes to a stop in8 s.Round all

your answers to one decimal place. (a) What was the car's acceleration? (b) How long would the car take to come to a stop starting from 27 m/s with the same acceleration? (c) How long would the car take to slow down from 27 m/s to 22 m/s with the same acceleration? (a) The car's acceleration ism/s².? (b) The time the car would take to come to a stop starting from27 m/swith the same acceleration iss? (c) The time the car would take to slow down from27 m/sto22 m/s with the same acceleration is s?

6.A car is moving at4 m/swhen it begins to be accelerated at3.4 m/s². (a) How long does the car take to reach a speed of7 m/s?

(b) Howfar does it go during this period?

Round thefinal answers to one decimal place. (a) The time taken by car to reach a speed of 7 m/s is

s.? (b) The distance traveled during that time ism?

7.Round your answers to three significant figures. The driver of a train moving at24 m/s

applies the brakes when it passes an amber signal.The next signal is1 km

down the track and the train reaches it 78 s later.(a) Findthe train's acceleration and (b) its speed at the next signal. (a)a=?

m/s² (b)v₂=?

m/s

8.A car starts from rest and covers1,025 m (very nearly5/8 mi) in21 s.Find theaverage acceleration of the car and its final speed.Round theanswers to two decimal places. The average acceleration of the car is

m/s².? The final speed of the car is

m/s.?

9.At the same instant one stone is thrown horizontally from a cliff while an identical one is dropped.

Which is true of their relative times of impact, velocities, and accelerations?

-	The dropped stone experiences less acceleration, the thrown stone hits first with a greater velocity.
-	The two stones experience the same acceleration and strike at the same time, however the stone thrown horizontally has a greater velocity because of its horizontal component.
-	The two stones experience the same acceleration, they hit at the same time with the same velocity.
-	The thrown stone experiences a greater acceleration, however, the two stones hit at the same time with the same velocity.

10.Round your answer to three significant figures. A ball dropped from the roof of a building takes3 sto reach the street. How high is the building? h= m?

11.A ball is thrown downward at2 m/s. What isits speed0.5 slater?Round youanswer to one decimal place. m/s?

12.When will a stone thrown vertically upward at9.9 m/sreach the ground?t=?

13.Carry out all calculations to at least 3 decimal places. A ball is thrown vertically upward with an initial speed of13 m/s.(a) Howlong will it take the ball to reach the highest point in its path?(b) Howlong will it take the ball to return to its starting place?(c) Whatwill the ball's speed be there? (a) Time taken by the ball to reach the highest point is

s. ? (b) Time taken by the ball to return to its starting place is

s. ? (c) Final speed after falling from the highest point is. m/s ?

14.Carry out all calculations to at least 3 decimal places. A ball is thrown vertically upward with an initial speed of37 m/s.

(a) Howlong will it take the ball to reach the highest point in its path?

(b) How long will it take the ball to return to its starting place?

(c) Whatwill the ball's speed be there? (a) Time taken by the ball to reach the highest point is?

s. (b) Time taken by the ball to return to its starting place is?

s. (c) Final speed after falling from the highest point is?