In the first law, an object will not change its motion unless a force acts on it. In the second law, the force on an object is equal to its mass times its acceleration. In the third law, when two objects interact, they apply forces to each other of equal magnitude and opposite direction
Answered using calculus.
Antidifferentiated the acceleration to get velocity. Added variable c as we do not know if there was an extra number there yet.
Knowing that when time is 0, the velocity is 20, we can substitute those numbers into the equation and find that c = 20.
Now we have full velocity equation: v = 1.5t + 20
Now we substitute 4 into t to find out the velocity after 4 seconds. This gives us the final answer of 26m/s
Answer:
Newton's law of universal gravitation is usually stated as that every particle attracts every other particle in the universe with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
Answer:
390 N
Explanation:
The net acceleration is:
a² = aₓ² + aᵧ²
a² = (900 m/s²)² + (870 m/s²)²
a = 1250 m/s²
So the net force is:
F = ma
F = (0.31 kg) (1250 m/s²)
F = 390 N
Answer: 5 m
Explanation:
We have the following data:
is the intensity of the sound at 7.5 m from the source
is the distance at which the intensity
was measured
is the intensity of the sound at
from the source
We have to find 
Since the object is radiating the signal uniformly in all directions, we can use the <u>Inverse Square Law for Intensity:</u>

Isolating
:


This is the distance at which the intensity is the "threshold of pain"
Now, we have to substract this value to
to find how much closer to the source can we move:
