Answer:
It measure the effort it takes for an object to move
Explanation:
Work done is the force applied to move a body through a particular distance.
It can also to be said to be a measure of the effort it takes for an object to move.
The unit of work done is in Joules.
To find work done, we use the expression below:
Work done = Force x distance
Answer:

Explanation:
From the question we are told that:
Beat frequency 
Frequency 
Generally the equation for Frequency of the violin is mathematically given by



Therefore the period of the violin string oscillations is



Answer:
Scientists have identified about a dozen major and several minor tectonic plates
Answer:
Explanation:
The direction of propagation of electromagnetic wave
is given by the direction of vector E x B where E is electrical field , B is magnetic field .
Given Electric field = E i because it is along x axis
Magnetic field = Bj because it is along y axis
E x B = Ei x Bj
= EB k .
so direction of E x B is along k direction or z - axis so wave is propagating along z - axis .