Question

5. A car starting from rest moves in a straight line with a constant acceleration of 2.20 m/s? for 14.0 s, then slows down to a stop with a deceleration of 2.90 m/s2. How far does it travel? constant meters 6. Two cars are traveling along a straight road. Car (A) maintains a constant speed of 890 kmh; car (B) maintains a constant speed of 115 km/h. Att o, car (B) is 39.0 km behind car A. How far will car (A) travel fromt 0 before it is overtaken by car (B)? km 7. A ball is thrown vertically downward from the edge of a bridge 29 5 m high with an initial speed of 18.0 m/s. The ball falls all the way down and strikes the water below. Determine the time it takes the ball to strike the water. 8. A photographer in a helicopter ascending vertically at a constant rate of 1.3 m/s accidentally drops a camera out the window when the helicopter is 54.0 m above the ground. (a) How long will it take the camera to reach the ground? 9.(b) What will its speed be just before it hits the ground? m/s

Answer 1

Distance covered in 14 se from s = ut + 1/2 at^2 s_1 = 0 + 1/2 times 2.2 times 14^2 s_1 = 215.6 m distance covered in remaining part of journey from v = u + at v = 0 + 2.2 times 14 v = 30.8 m/s from v^2 - u^2 = 2as 0^2 - (30.8)^2 = -2 times 2.9 times s_2 s_2 = 163.56 m total distance s = s_1 + s_2 = 215.6 + 163.56 s = 379.16 m