The restoring force in a simple harmonic oscillator acts as a restoring force, acting opposite in direction of and proportional in magnitude to the displacement. This has the result that when the oscillator reaches the equilibrium point, it has gained its maximum kinetic energy (and therefore velocity) while the magnitude of the restoring force, and therefore the acceleration, is 0.
Choice A
Answer:
A. 231.77 J
B. 5330.71 J
C. 46 donuts
Explanation:
A. To lift the barbell once, she will have to extend it the full length of her arm. The work done will then be:
W = F * d
Where the force is the weight of the barbell.
F = m * g
Hence, the work done in lifting the barbell is:
W = m * g * d
W = 43 * 9.8 * 0.55
W = 231.77 J
B. If she does 23 repetitions, the total energy she expend will be equal to the Potential energy when the barbell is lifted multiplied by 23:
E = 23 * m * g * d
E = 23 * 231.77
E = 5330.71 J
C. 1 Joule = 4.184 calories
5330.71 Joules = 5330.71 * 4.184 = 22303.69
If 1 donut contains 490 calories, the number of donuts she will need will be:
N = 22303.69/490 = 45.5 donuts or 46 donuts
The answer is 9.8, did this last year in AP Science
a hypothesis is given to explain a phenomena which has not been explained earlier.
it can proved by an experiment if that experiment gets the other results regarding that particular phenomena in agreement with that being predicted by the hypothesis and if result doesnt match the prediction then the hypothesis is again totally discarded at times.