Simple Machines, Power and Work

How can you decrease the effort force needed to push a weight to the top of the ramp?

• cover the surface with carpet

• increase the length of the ramp

• increase the height of the ramp

• decrease the length of the ramp

Tags

NGSS.MS-PS2-2

Calculate the mechanical advantage in using the lever to move the car if the car weighs 9000N, the effort force is 300N.

• 3

• 30

• 300

• 9

A flat sloping surface that connects lower and higher elevations. It makes raising objects easier.

• wedge

• inclined plane

• lever

• pulley

Tags

NGSS.MS-PS2-1

MA is always greater than one in ....... class lever

Work done by effort in a machine is called ..........

A crowbar is lifting a load of 500N by using an effort of 250N.It's MA is ..........

Tags

NGSS.MS-PS2-2

Velocity ratio of a lever is calculated by using the formula

• VR=Ld / Ed

• VR= Ed/ Ld

• VR= Ld x Ed

• VR= Ed x Ld/2

The value of VR of a machine is always greater than the value of MA because

• MA is not affected by friction

• VR is not affected by friction

• MA is affected by friction

• VR is affected by friction

A third class lever makes our work easier.

• By multiplying the force applied.

• By accelerating work.

• By changing direction.

• Both option 2 and 3

Pradeep sits on one end of a see-saw and Prasoon sits on the other. Pradeep goes up in the air and Prasoon stays down on the ground. In order for prasoon to make Pradeep move down, he should

• stand on the board

• push down on the board

• move towards the center

• move away from the center

Tags

NGSS.MS-PS2-2