Answer:
1.5 m/s
Explanation:
Momentum is conserved and conservation of momentum is
p₁ + p₂ = p'₁ + p'₂
or
m₁v₁ + m₂v₂ = m₁v'₁ + m₂v'₂
In our problem, after collision v'₁ will be equal to v'₂.
Since objects are identical m₁ = m₂
m(v₁+ v₂) = 2m x v'₁
(2m/s + 1m/s) = 2v'₁
v'₁ = v'₂ = 1.5 m/s
the relation that relates the speed of wave, frequency of wave and wavelength is given as
wavelength = 
the speed of wave in a medium remains constant. hence the wavelength is inversely related to the frequency of wave.
that means, as the frequency is increased, the wavelength decreases and vice versa.
hence the correct choice is
B decreases
3 times 6= 18. The average speed is 19 mph.
hope this helps!
Answer:
Explanation:
When we apply a horizontal force of 76 N to a block, the block moves across the floor at a constant speed. So net force on the block is zero .
It implies that a force ( frictional ) acts on it which is equal to 76 N in opposite direction ( friction )
When we apply a greater force on it it starts moving with acceleration .
This time kinetic friction acts on it due to rough ground equal to 76 N .This is limiting friction ( maximum friction )
Net force on the body in later case
= 89 - 76
= 13 N
Force by ground on the block in horizontal direction = 76 N ( FRICTIONAL FORCE )
=