I think it's D. Options C and D are true. The graph shows an increase in speed from points 6 to 12, which means Option C is true. It shows an even bigger increase in speed from points 24 to 30, and since bikes go faster when traveling downhill, I would think that Option D was correct as well.
Equal because the book is not moving and the forces are balanced/equal
Answer: Cannot determine cause we need to know the change of time to calculate the work.
Explanation:
m = 0.5kg
V = 3m/s - 5m/s = -2m/s
P = W/t = Fv
F = ma
W = Fvt
W = (0.5)(9.8)t = 4.9t
An impact which stops a moving object must do enough work to take away its kinetic energy, so extending the distance moved during the collision reduces the impact force.
Answer:
0.495m
Explanation:
The kinetic energy of the stone will be equal to the work done by the spring
Mathematically;
W = KE
1/2ke² = 1/2mv²
ke² = mv²
k is the spring constant = 150N/m
e is the extension
m is the mass = 0.015kg
v is the velocity = 70m/s
Substitute
150e² = 1/2 * 0.015 * 70²
150e² = 36.75
e² = 36.75/150
e² = 0.245
e = √0.245
e = 0.495m
Hence the extension of the catapult is 0.495m
