Answer:
15.2 s
Explanation:
Convert hp to W:
55.0 hp × 746 W/hp = 41,030 W
Power = energy / time
41030 W = 6.22×10⁵ J / t
t = 15.2 s
v^2 = v0^2 +2ad
v^2 = 22^2 + 2*3.78*45 = 824.2
v= √824.2 = 28.7 m/s
Answer:
2.667m/s to the north and 3.333 m/s to the west
Explanation:
According to law of momentum conservation, the total momentum should be conserved before and after the explosion.
Before the explosion, the momentum was
0.5*2 = 1 kg m/s to the west
Therefore the total momentum after the explosion should be the same horizontally and vertically.
Vertically speaking, it was 0 before the explosion. After the explosion:
0.2*4 + 0.3v = 0
0.3v = -0.8
v = -0.8/0.3 = -2.667 m/s
So the vertical component of the 0.3kg piece is 2.667m/s to the north
Horizontally speaking, since the 0.2kg-piece doesn't move west or east post-explosion:
0.2*0 + 0.3V = 1
0.3V = 1
V = 1/0.3 = 3.333 m/s
So the horizontal component of the 0.3kg piece is 3.333 m/s to the west
Heat comes from the movement of molecules so it's B