Answer:8 m/s
Explanation:
Given


kinetic Energy of 
initially
is at rest and let say
is moving with velocity u
kinetic Energy of 


In Completely inelastic collision both mass stick together and move with common velocity
Suppose v is the common velocity


therefore Final velocity with which both blocks moves is 1 m/s
Answer:
"The distance between crests is 3 cm."
Explanation:
If he writes down "The distance between crests is 3 cm."
That means he is describing the wavelength of a wave and not longitudinal wave. He ought to write something about " direction "
Longitudinal waves are waves in which the displacement of the medium is in the same direction as, or parallel to, the direction of propagation of the wave. While
Wavelength is the distance between the two successfully Crest or trough
Answer:
Yes it is possible to control to some extent.
Explanation:
In general there are two types of magnets : permanent and temporary (electromagnets).
Electromagnets can be controlled since it basically depends on electricity. By switching on and off the electric supply the magnets also can be switched on and off respectively. We can also control the intensity of magnetic power.
On the other hand permanent magnet cannot be switched on and off but the magnetic properties can be altered event to an extent when it loses all its magnetic properties. It can be caused by high temperature, physical impact and also exposure to other magnetic fields. For every element there is a point of temperature called curie temperature above which the permanent magnet loses its magnetic properties. This can be brought back again by induced magnetism. The only issue is that induced magnetism work in most cases but not in all.
Answer:
Force is repulsive hence direction of force is away from wire
Explanation:
The first thing will be to draw a figure showing the condition,
Lets takeI attractive force as +ve and repulsive force as - ve and thereafter calculating net force on outer left wire due to other wires, net force comes out to be - ve which tells us that force is repulsive, hence direction of force is away from wire as shown in figure in the attachment.