Answer:
Explanation:
Machines simply make work easier to do. They increase the amount of force exerted on a body and also the distance through which the force is applied. Also, they can also change the direction through which force on them is applied in order to produce much more work.
Work done = force x distance
The input force in a machine is attenuated to yield even more force. This is the purpose of designing a simple machine. When the force increases, more work would be produce with our little effort applied on the body.
Work done is a function of the force applied on a body and the distance through which it moves.
Answer:
Maximum permitted surface crack length is 1.29 mm
Explanation:
As per the question:
Tensile stress, 
Surface energy of magnesium oxide, SE = 
Modulus of elasticity of the material, E = 225 GPa = 
Now,
To calculate the maximum allowable surface crack length:


Answer:
Explanation:
Given
Sphere of Radius R
Suppose mass of block is m
At any instant \theta Normal reaction(N) and weight(mg) is acting such that
, where v is velocity of block at any angle \theta
When block is just about to leave then N=0
therefore

-------------------1
Also by conserving Energy we get
Potential Energy=kinetic Energy of block

here h=vertical distance traveled by block
From diagram



-----------------2
From 1 and 2



Thus from this value of h is


