Answer:
a) 0.323m/s b) 54.278 m/s
Explanation:
The shell is moving upward with a speed of 17m/s
1.7s after it was launch
Using equation of motion on a straight line,
Vfinal = Vintial + acceleration due to gravity *time
Where V represent the speed(velocity)
Vinital = V(at 1.7s) - 9.81* 1.7
Vinital = 17 - 16.677
a) Vinital = 0.323m/s
b) using the same equation,
V(after 5.5s) = Vinital + 9.81*5.5s
Vafter5.5s = 0.323 + 53.955
V after 5.5s = 54.278m/s
Answer:
(a)
(b) It is moving at 14 m/s.
Explanation:
(a)
Given:
The energy, , of an object moving with a velocity is given as:
, where, is its mass.
Multiplying both sides by 2, we get
Now, divide both sides by
Taking square root both sides, we get
Therefore, in terms of and is given as:
(b)
Using the above formula,
Plug in 4900 joules for and 50 kg for . Solve for . This gives,
Therefore, it is moving with a speed of 14 m/s.
Work or energy spent=force times distance=25N*4m=100Nm
power=energy or work divided by time=100Nm/5s=20Nm/s