# Question: In laboratory situations a projectile s range can be used to

In laboratory situations, a projectile’s range can be used to determine its speed. To see how this is done, sup-pose a ball rolls off a horizontal table and lands 1.5 m out from the edge of the table. If the tabletop is 90 cm above the floor, determine

(a) The time the ball is in the air, and

(b) The ball’s speed as it left the table top.

(a) The time the ball is in the air, and

(b) The ball’s speed as it left the table top.

## Answer to relevant Questions

A stone thrown off a bridge 20 m above a river has an initial velocity of 12m/s at an angle of 45o above the horizontal (Fig. 3.33). (a) What is the range of the stone? (b) At what velocity does the stone strike the water? ...The apparatus for a popular lecture demonstration is shown in Fig. 3.35. A gun is aimed directly at a can, which is released at the same time that the gun is fired. This gun won’t miss as long as the initial speed of the ...A shopper is in a hurry to catch a bargain in a department store. She walks up the escalator, rather than let-ting it carry her, at a speed of 10 m relative to the escalator. If the escalator is 10 m long and moves at a ...A boat that travels at a speed of 6.75 m/s in still water is to go directly across a river and back (Fig. 3.38). The current flows at 0.50 m/s. (a) At what angle(s) must the boat be steered? (b) How long does it take to ...An airplane is flying at 150 mi/h (its speed in still air) in a direction such that with a wind of 60.0 mi/h blowing from east to west, the airplane travels in a straight line southward. (a) What must be the plane’s ...Post your question