A 25-N steel ball is suspended by a light rope from the ceiling and the system i
ID: 1837466 • Letter: A
Question
A 25-N steel ball is suspended by a light rope from the ceiling and the system is not moving. The tension in the rope is 25 N 25gN zero can't decide without acceleration information Work is done when a net force is applied to an object over a certain distance True false A 2kg block is lifted vertically 0.5 m by a construction worker How much work was done by the construction worker? 1 J 10 J 0.1J zero If a person does 50 J of work In mowing a 30kg box over a 10m distance on a horizontal surface, what Is the minimum force required? 0.2 N 1.66N 3N 5N A certain motor is able to perform 6000 J of work over the course of 2 minutes. What power is developed by the motor during this time? 50 W 3000W 12000W 3000J 50J A 6.0-kg block Is released from rest 80m above the ground. When it has fallen 50 meters It's potential energy is approximately: 4800 J 3500 J 2940J 1764J 600J A 78-kg skydiver has a speed of 62 m/s at an altitude of 870 m above the ground Determine the kinetic energy possessed by the skydiver. 3.9 Times 10^3 J 1.5 Times 10^5 J 2.4 Times 10^4 J 2.7 Times 10^4 J A 78-kg skydiver has a speed of 62 m/s at an altitude of 870 m above the ground. Determine the potential energy possessed by the skydiver 6.7 Times 10^5 J 1.5 Times 10^5 J 4.2 Times 10^6 J 8.1 Times 10^5 J What is the mass of an object that moves 10 meters in 2 seconds, and has a momentum of 10 Ns? 1 kg 2 kg 5 kg 10 kg The collision of two pool balls is approximately what kind of collision? Inelastic Elastic Completely inelastic Depends on the nature of the collision A particle of 1 kg mass moving at a velocity of 50 m/s hits a particle of 1 kg mass al rest in an elastic collision. What is the final velocity of the second particle? 0 25 m/s 100 m/s 50 m/s You tie a rock to a string and whirl it in a horizontal circle. The string breaks. In the absence of gravity, the rock... Travels in a circle Flies in a straight line vertically up into the air Travels in a straight line horizontally away from you ExplodesExplanation / Answer
22. ball is in equilibrium,
T -mg = 0
T = mg = 25 B ....Ans(A)
23. True.
24. W = m g h = 2 x 9.8 x 0.5 = 9.8 J Or 10 J
ans(b)
25. Work done = F.d
50 = F(10)
F = 5 N
Ans(d)
26. P = work done / time
P = (6000 J) / (2 x 60 sec) = 50 Watt
ans(A)
27. P = m g h = 6 x 9.81 x (80 - 50) = 1764 J
Ans(d)
28. KE = m v^2 / 2 = 78 x 62^2 / 2 = 1.5 x 10^5 J
Ans(b)
29. PE = 78 x 9.81 x 870 = 6.7 x 10^5 J
Ans(a)
30. v = 10/2= 5 m/s
momentum = m v
10 = m (5)
m = 2 kg
32. when mass is same then velocity interchanges.
Ans (d)
33. (C)
rock will move in the direction of velocity it has at the time string breaks.