Answer:
Rest and motion are the relative terms because they depend on the observer's frame of reference. So if two different observers are not at rest with respect to each other, then they too get different results when they observe the motion or rest of a body.
Answer:
15 N
Explanation:
According to Newton's third law of motion, to every action, there is an equal and opposite reaction. This reaction is equal in magnitude to the force acting but in an opposite direction.
Now, if the book weighs 15 N, an opposite equal force will be: N = -15 N
But the magnitude of this will be the absolute value which is 15N.
Answer:
The truck's speed is 4.04 m/s.
Explanation:
Given that,
Emit frequency = 600 Hz
Beat = 7.00 beat/sec
We need to calculate the truck's speed
Using formula of speed
Where, v = speed of sound
Put the value into the formula
Hence, The truck's speed is 4.04 m/s.
Answer:14 m/s
Explanation:
Kinetic energy(ke)=175J
Momentum(M)=25kgm/s
Speed=v
Mass=m
Ke=(m x v x v)/2
175=(mv^2)/2
Cross multiply
175 x 2=mv^2
350=mv^2
Momentum=mass x velocity
25=mv
m=25/v
Substitute m=25/v in 350=mv^2
350=25/v x v^2
350=25v^2/v
v^2/v=v
350=25v
v=350/25
v=14 m/s
