Physics Work,Power & Energy Level: High School
A 1.71 kg ball is attached to a ceiling by a 1.96 m long string . The height of the room is 3.16 m .a) What is the gravitational potential energy of the ball relative to the ceiling ?
b) What is the gravitational potential energy of the ball relative to the floor ?
Physics Work,Power & Energy Level: High School
How long will it take a 1750 W motor to lift a 272 kg piano to a sixth-story window 13.6 m above ?
Physics Work,Power & Energy Level: High School
A 50.3 kg student climbs a 5.10 m long rope and stops at the top .a) What must her average speed in order to match the power output of a 120 W lightbulb ?
b) How much work does she do ?
Physics Work,Power & Energy Level: High School
A 77.9 g arrow is fired from a bow whose string exerts an average force of 99.8 N on the arrow over a distance of 79.2 cm . What is the speed of the arrow as it leaves the bow ?
Physics Work,Power & Energy Level: High School
On a frozen pond , a 14.1 kg sled is given a kick that imparts to it an initial speed of Vo = 1.70 m/s . The coefficient of kinetic friction between sled and ice is mu^k = 0.105 . Use the work kinetic energy theorem to find the distance the sled moves before coming to rest .
Physics Work,Power & Energy Level: High School
A 260 kg piano slides 4.14 m down a 32.4 degree incline and is kept from accelerating by a man who is pushing back on it parallel to the incline. As seen in the figure at “click here” . The effective coefficient of kinetic friction is 0.370a). Calculate the work done by the man on the piano .
b). Calculate the work done by the force of gravity.
c). Calculate the work done by the force of gravity .
Physics Work,Power & Energy Level: High School
Particle in motion
A 0.632 kg particle has a speed of 2.28 m/s at point A and kinetic energy of 7.83 J at point B .a) What is its kinetic energy at A ?
b) What is the total work done on the particle as it move from A to B ?
Physics Work,Power & Energy Level: High School
A block of mass 2.30 kg is pushed 2.29 m along a frictionless horizontal table by a constant 18.0 N force directed 23.6 degree below the horizontal . Determine the work die by the applied force .
Physics Work,Power & Energy Level: High School
A 754 N marine in basic training climbs a 12.5 m vertical rope at a constant speed in 6.6 s . What is the power output ? Answer in units of W
Physics Work,Power & Energy Level: High School
A weight lifter lifts a set of weights a vertical distance of 3.95 m . If a constant net force of 355 N is exerted on the weights , how much net work is done on the weights ? Answer in units of J .
Physics Work,Power & Energy Level: High School
A 20 g bullet is accelerated in a rifle barrel 89.6 cm long to a speed of 686 m=s . Use the work energy theorem to solve the problem . The average force exerted on the bullet while it is being accelerated . Answer in units of N .
Physics Work,Power & Energy Level: High School
It is uncommon during the service of a professional tennis player for the racket to exert an average force of 158 N on the ball . Assume that the ball starts from rest . The ball has a mass of 0.0608 kg and is in contact with the strings of the racket for 0.029 s . What is the kinetic energy of the ball as it leaves the racket ? Answer in units of J .
Physics Work,Power & Energy Level: High School
A 2.54 kg car has a speed of 11.7 m /s , The car then hits a tree . The tree doesn’t move and the car comes to rest . Find the change in kinetic energy of the car .(a) Find the amount of work done by the car as its front is pushed in . Answer in units of J .
(b) Find the magnitude of that pushed .
Physics Work,Power & Energy Level: High School
When a rattlesnake strikes , its head accelerates from rest to speed of 32 m=s in 0.58 s seconds . Assume for simplicity that the only moving part of the snake is its head of mass 140 g .How much (average) power does the rattlesnake need to accelerate its head that fast ?
Physics Work,Power & Energy Level: High School
A 500 kg cart , including the passengers , is initially at rest . When the spring is released , the cart is launched for a trip around the loop-the-loop whose radius is 10 m . Determine the distance the spring of force constant 68000 N/m must be compressed in order that carts speed at the top of the loop is 12 m/s . Ignore friction . Assume that g = 10 m/s^2 .