The force of gravity is much weaker than the strong nuclear force. But the strong nuclear force only acts over short distances, such as within the nuclues. The gravitational force can act over infinite distance.
Sound waves travel faster through <em>solids</em> than they do through gases or liquids. <em>(C) </em>They don't travel through vacuum at all.
Example:
Speed of sound in normal air . . . around 340 m/s
Speed of sound in water . . . around 1,480 m/s
Speed of sound in iron . . . around 5,120 m/s
For this case we have that by definition, the average power is given by:
Where:
W: It is the work done
t: It's time
According to the data we have to:
So:
Answer:
Answer:
C
Explanation:
momentum = mass ×velocity
A. mv = 200
B. mv = 300
C. mv= 400
D. mv= 200
highest is C.
Answer:
- Newton's first law applies. An object at rest will stay that way until a force is applied.
- Any amount of effort can be applied to any amount of mass (in the ideal case). The question is not sufficiently specific.
Explanation:
A force is required to move an object because the object will stay at rest until a force is applied.
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The effort required to lift or push two masses instead of one depends on the desired effect. For the same kinetic energy, no more effort is required. For the same momentum, half the effort is required for two masses. For the same velocity, double the effort is required.
