#1
As we know that energy of electromagnetic wave is given by
so here we know that penetrating power will directly depends on its energy and energy inversely depends on wavelength
So here we can say correct answer will be
C) The penetrating power decreases as the wavelength increases.
#2
Speed of sound is maximum in solids and minimum in gas
so here as ice melts into water the speed of sound must have to decrease
so correct answer will be
D) The speed of sound would decrease because sound travels faster through solids than liquids.
#3
mechanical waves required medium to travel while non mechanical waves do not require any medium to travel
so here correct answer will be
A) sound
Answer:
Explanation:
A component of 150 N in vertical direction will reduce the magnitude of reaction force.
reaction force exerted by the floor
= mg - 150 sin 30
where m is mass of the crate .
the magnitude of the horizontal component of the 150-newton force
150 cos30
= 130 N
This force tries to pull the crate in forward direction with acceleration but it has no acceleration . It is so because frictional force of equal magnitude acts on it in opposite direction which makes the net force acting on it equal to zero.
Hence frictional force is equal to 150 cos 30.
= 130 N .
Answer:
The solution is given in the picture attached below
Explanation:
Answer:
e. all of these
Explanation:
The fatigue strength is improved by then high alloy steels , high yield steels , high hardened steel , high ultimate steel .
Due to the formation of the improved materials in alloy steels will increase the fatigue strength . Similarly for a high yield steels and hardened steels these cycles to failure will improve .
