Machines
Formula of efficiency?
output work divided by input work x 100%
The force must be applied in the same direction as the...
Movement
Forces are measured in...
Newtons
Formula of Power?
P= w/t
How can a mass gain velocity?
By gravity
TRUE OR FALSE
The work of pulling the box will be easier if the man uses the ramp.
False
What is the formula of work?
work= force x distance
What is force?
A force is a push or pull upon an object resulting from the object's interaction with another object.
To lift a baby from a crib, 75J of work is done. How much power is required to lift the baby in 0.6s?
125W
Formula of Momentum?
P= m·v
TRUE OR FALSE
The ramp helps the man do work by reducing input distance
False
How much work is done when you push a shopping cart with a force of 50N for a distance of 5m?
250J
Force creates, stops or...
modifies a movement.
What is power?
Power is the rate of doing work, the amount of energy transferred per unit time.
What is momentum?
Force or speed of movement
Any of the basic mechanical devices for applying a force, such as an inclined plane, wedge, or lever.
During the Powerhouse lab, Jerome runs up the stairs, elevating his 102kg body a vertical distance of 2.29mts. How many work is done?
2289.084J
What is the force on a 1000 kg elevator that is falling freely at 9.8 m/sec2?
9,800N
A 120-kg linebacker accelerates from 5.0 m/s to 10.0 m/s in 1.0 s. How much power does that require?
4,500W
A particle has a mass of 10 kg and a velocity of 5 m/s. What is the momentum of the particle?
50 kg·m/s
Which are the types of simple machines?
Lever, inclined plane, wedge, pulley, wheel & axle, and screw
What is work?
The measure of energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement.
An object of mass 30 kg is falling in air and experiences a force due to air resistance of 50 newtons. Determine the net force acting on the object and calculate the acceleration of the object.
Net Force: 244N
Acceleration: 8.13 m/s2
You’re driving a snowmobile that accelerates from 10 m/s to 20 m/s over a time interval of 10.0 s. If you and the snowmobile together have a mass of 500 kg, how much power is used?
7,500W
What is conservation of momentum?
Is something which doesn't change. This means that the variable in an equation which represents a conserved quantity is constant over time.