Thanks to your slides, it help me understand the science concept on work,energy and power..I chose, and used some of the slides in my G8 science. I made some edit fitted to my slow learner students...It helps me save time in preparing my lessons.. God bless you..!
Work – the product of force and displacement, as long as they are both in the same direction.
This is a vector times a vector. In this case, a vector times a vector gives a scalar . Work is measured in Joules (J) which is the same as a Newton x meter.
As Alex pulls his red wagon down the sidewalk, the handle of the wagon makes an angle of 60 o with the pavement. If Alex exerts a force of 100 Newtons along the direction of the handle, how much work is done when the displacement of the wagon is 20 meters along the ground?
A constant force of 50 Newtons is applied over a distance of 10 meters. Draw a graph to represent this information. Calculate the work done by this force. Calculate the area under the graph. How do they compare?
A 200 Newton force is applied to an object that moves in the direction of the force. If the object travels with a constant velocity of 10 m/s, calculate the power expended on the object.
A 10kg object subjected to a 20 Newton force moves across a horizontal frictionless surface in the direction of the force. Before the force was applied, the speed of the object was 2.0 meters per second. When the force is removed, the object is traveling at 6.0 meters per second. Calculate the following quantities: (a) KE 1 (b) KE 2 (c) Δ KE (d) W and (e) distance.
A 2.0 kilogram mass is lifted to a height of 10 meters above the surface of the Earth. Calculate the change in the gravitational potential energy of the object.
In the system, the sum of the potential energy and kinetic energy will be conserved; a change in one is accompanied by an opposite change in the other.
A 2.0 kg ball is tossed with a velocity of 4.0 m/s straight into the air. How high does the ball travel upwards? Calculate the initial kinetic energy of the ball. Calculate the potential energy of the ball at it’s peak.
A pendulum whose bob weighs 12 Newtons is lifted a vertical height of 0.40 meter from its equilibrium position. Calculate the change in potential energy between maximum height and equilibrium height, the gain in kinetic energy, and the velocity at the equilibrium point.