Answer:
B) 20N.s is the correct answer
Explanation:
The formula for the impulse is given as:
Impulse = change in momentum
Impulse = mass × change in speed
Impulse = m × ΔV
Given:
initial speed = 40m/s
Final speed = -60 m/s (Since the the ball will now move in the opposite direction after hitting the bat, the speed is negative)
mass = 0.20 kg
Thus, we have
Impulse = 0.20 × (40m/s - (-60)m/s)
Impulse = 0.20 × 100 = 20 kg-m/s or 20 N.s
Answer:
The correct answer is option b. At higher elevations, it would take longer to hard boil an egg, because there is a lower boiling.
Explanation:
When we boil water at a very high temperature, it turns out that the water boils much faster. This is because the higher we are, <u>there will be less oxygen and less pressure in the atmosphere</u>. This implies that the water vapor becomes steam much faster than as it happens at low temperatures, so less heat will be needed for the water to boil.
That is why <u>if we want to cook an egg, we will have to lower the heat</u> of the kitchen when we put it on the fire, in order to avoid boiling water very quickly. Lowering the heat, <u>then cooking the egg will take much longer.
</u>
Given this data, the correct answer is option B, At higher elevations, it would take longer to hard boil an egg, because there is a lower boiling.
The motion of falling objects is the simplest and most common example of motion with changing velocity. The early pioneers of physics had a correct intuition that the way things drop was a message directly from Nature herself about how the universe worked. Other examples seem less likely to have deep significance. A walking person who speeds up is making a conscious choice. If one stretch of a river flows more rapidly than another, it may be only because the channel is narrower there, which is just an accident of the local geography. But there is something impressively consistent, universal, and inexorable about the way things fall.
It is force because work/distance= force
