I think B is the most correct, because logically it's harder to bend a stiffer spring than it is to bend a softer one. Also, I don't think length comes into play. So B.
Answer:
2.1 cm
Explanation:
The general equation for the graph is:
y = A cos(ωt + ∅)
A: amplitude, is the maximum and minimum value for y(t)
Answer:
True
Explanation:
It may be seen as a statement about inertia, that objects will remain in their state of motion unless a force acts to change the motion. Any change in motion involves an acceleration, and then Newton's Second Law applies.
- Hyperphysics
Answer:
(c) is accelerating upward
Explanation:
When a person stand in an elevator moving upwards, he feels heavier because the elevator's floor presses harder on his feet, and the scale will show a higher reading than when the elevator is at rest.
According to Newton's second law
R = mg + ma
where;
R is the reading of the scale = apparent weight of the person
mg is the normal weight of the person
ma is the upward force acting on the person
Therefore, his apparent weight will be the greatest when the elevator is accelerating upward
(c) is accelerating upward
Answer:
6.86 meters
Explanation:
Let the compression of the string be represented by x, and the height of projection of the toy rocket be represented by h.
So that;
x = 9 cm = 0.09 m
In its rest position (i.e before the launch), the spring has a stored potential energy which is given as;
PE = K
= x 830 x
= 415 x 0.0081
= 3.3615
The potential energy in the string = 3.36 Joules
Also,
PE = mgh
where: m is the mass, g is the gravitational force and h the height.
m = 50 g = 0.05 kg, g = 9.8 m
Thus,
PE = 0.05 x 9.8 x h
3.3615 = 0.05 x 9.8 x h
3.3615 = 0.49h
⇒ h =
= 6.8602
The height of the toy rocket would be 6.86 meters.