Kinetic energy lost in collision is 10 J.
<u>Explanation:</u>
Given,
Mass, 
= 4 kg
Speed, 
= 5 m/s
= 1 kg
= 0
Speed after collision = 4 m/s
Kinetic energy lost, K×E = ?
During collision, momentum is conserved.
Before collision, the kinetic energy is
By plugging in the values we get,
K×E = 50 J
Therefore, kinetic energy before collision is 50 J
Kinetic energy after collision:
Since,
Initial Kinetic energy = Final kinetic energy
50 J = 40 J + K×E(lost)
K×E(lost) = 50 J - 40 J
K×E(lost) = 10 J
Therefore, kinetic energy lost in collision is 10 J.
Answer:
Fnet = 0
Explanation:
- Since the block slides across the floor at constant speed, this means that it's not accelerated.
- According Newton's 2nd Law, if the acceleration is zero, the net force on the sliding mass must be zero.
- This means that there must be a friction force opposing to the horizontal component of the applied force, equal in magnitude to it:
- In the vertical direction, the block is not accelerated either, so the sum of the normal force and the vertical component of the applied force, must be equal in magnitude to the force of gravity on the block:
⇒ 169 N + Fn = Fg = 216 N (3)
- This means that there must be a normal force equal to the difference between Fappy and Fg, as follows:
- Fn = 216 N - 169 N = 47 N (4)
Both verbs come from Olde English.
That's why everybody clearly understood their meaning until
a hundred years ago, but nobody understands them now.
"Waxing" = growing
For two weeks after the New Moon, it's growing toward Full.
First it's a waxing crescent for a week, then it's waxing gibbous.
"Waning" = shrinking
For two weeks after the Full Moon, it's shrinking toward New.
First it's waning gibbous for a week, then it's a waning crescent.
