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 wooden floor exerts a greater force to give the same impulse as a padded mat.
Explanation:
-The wooden floor exerts a greater force for the same impulse as the padded mat.
-Unlike the wooded floor, the padded mat absorbs some of the energy when you fall. This in turn makes it exert less force on the body during the fall.
-Hence, you are less hurt when you fall on the padded floor.
Kinetic Energy = (1/2) (mass) (speed)²
KE = (1/2) (400 kg) (50 m/s)²
KE = (200 kg) (2500 m²/s²)
KE = 500,000 kg-m²/s²
<em>KE = 500,000 Joules</em>
KE = 1/2 Mega-Joule