Daniddmelo says it right there, don't know why he got reported.
The potential energy (PE) is mass x height x gravity. So it would be 25 kg x 4 m x 9.8 = 980 joules. The child starts out with 980 joules of potential energy. The kinetic energy (KE) is (1/2) x mass x velocity squared. KE = (1/2) x 25 kg x 5 m/s2 = 312.5 joules. So he ends with 312.5 joules of kinetic energy. The Energy lost to friction = PE - KE. 980- 312.5 = 667.5 joules of energy lost to friction.
Please don't just copy and paste, and thank you Dan cause you practically did it I just... elaborated more? I dunno.
The third choice.
The driver wants to see the object that is behind him. The light reflects off the mirror into the eyes of the driver portraying the object behind him
To find momentum you multiply the mass and velocity.
91 × 7 = 637 kg-m/s
From the calculations, the final momentum of B is 8.16 m/s
<h3>What is conservation of linear momentum?</h3>
According to the principle of the conservation of linear momentum, the momentum before collision is equal to the total momentum after collision.
This implies that;
MaUa + MbUb = MaVa + MaVa
Substituting values;
(0.08 kg * 0.5 m/s) + (0.05 kg * 0 m/s) = (0.08 kg * −0.1 m/s) + (0.05 kg * v)
0.4 = -0.008 + 0.05v
v = 8.16 m/s
Learn more about more about momentum: brainly.com/question/24030570:
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