I think it’s c because the other ones are just options not facts
Answer:
B
Explanation:
From Newton's law of motion, we have:
V^2 = U^2 + 2gH
Where V and U are final and initial velocity respectively.
H is the height.
For the object to have a sustain a maximum height it means the final velocity of the object is zero.
By computing the height of the object sustain by A, we have:
0^2 = 2^2 -2×10×H
0= 4 -20H
4 = 20H;
H= 0.2m
For object B we have;
0^2 = 1^2 -2×10×H
0 = 1 -20H
H = 1/20= 0.05m
From computing the height sustain by both objects, we see object B is projected at a shorter height into atmosphere than A.
Hence object B will return to the ground first.
The correct answer would be yes
Answer:
853776 J
Explanation:
The work-energy needs to pump water out of the pool is the product of the weight of water and distance h
E = Wh = mgh
Since water mass is a body of water we can treat it as the product of density 1000kg/m3 and volume, which is the product of base area and uniform height h
Therefore:
![E = mgh = g\rho A\int\limits^{2.2}_0 {h} \, dh\\E = 9.8*1000*30*12[h^2/2]^{2.2}_0 = 1764000(2.2^2 - 0^2) = 853776 J](https://tex.z-dn.net/?f=E%20%3D%20mgh%20%3D%20g%5Crho%20A%5Cint%5Climits%5E%7B2.2%7D_0%20%7Bh%7D%20%5C%2C%20dh%5C%5CE%20%3D%209.8%2A1000%2A30%2A12%5Bh%5E2%2F2%5D%5E%7B2.2%7D_0%20%3D%201764000%282.2%5E2%20-%200%5E2%29%20%3D%20853776%20J)
