A nut which can be broken by applying a force of 40 kgf is broken by using a nut cracker having its handle 20 cm long by placing it at a distance 2 cm from the hinge. The minimum force needed to break the nut.
4 kgf
5 kgf
2 kgf
3 kgf
A movable pulley is used as:
force multiplier
speed multiplier
device to change the direction of effort
all the above
Efficiency is :
MA x VR
Nut cracker is an example for:
Class I lever
Class II lever
Class III lever
Class I & II lever
The velocity ratio of Class III lever is:
50
less than 1
1
greater than 1
Raising a load by forearm is an example for:
None of these
The correct relationship between the voltage ratio (VR) distance moved by load (dL) and distance moved by effort (dE) is.
VR = dL + dt
VR = dE x dL
Class II levers are designed to have:
MA = VR
MA > VR
MA > 1
MA < 1
Which of the following statements is not true for a machine?
It always has efficiency less than 100 %.
Its mechanical advantage can be less than 1.
It can also be used as a speed multiplier.
It can have a mechanical advantage greater than the velocity ratio.
MA of a single fixed pulley is
2
0
5
