Kinetic Energy,K.E=1/2MV²
mass,m=16kg
velocity,v=4m/s
K.E=1/2×16×4²
=128kgm²/s²
=128 Joules
<span>the speed of something in a given direction. so i think none of these</span>
Gravity increased the downward speed (or decreases the upward speed) by 9.8 m/s every second.
21.2/9.8 = 2.2 seconds
Answer:

Explanation:
Given that
At X=0 V=Vo
At X=X1 V=0
As we know that friction force is always try to oppose the motion of an object. It means that it provide acceleration in the negative direction.
We know that



So the friction force on the box
Ff= m x a

Where m is the mass of the box.
The moment of inertia of a point mass about an arbitrary point is given by:
I = mr²
I is the moment of inertia
m is the mass
r is the distance between the arbitrary point and the point mass
The center of mass of the system is located halfway between the 2 inner masses, therefore two masses lie ℓ/2 away from the center and the outer two masses lie 3ℓ/2 away from the center.
The total moment of inertia of the system is the sum of the moments of each mass, i.e.
I = ∑mr²
The moment of inertia of each of the two inner masses is
I = m(ℓ/2)² = mℓ²/4
The moment of inertia of each of the two outer masses is
I = m(3ℓ/2)² = 9mℓ²/4
The total moment of inertia of the system is
I = 2[mℓ²/4]+2[9mℓ²/4]
I = mℓ²/2+9mℓ²/2
I = 10mℓ²/2
I = 5mℓ²