"At the bottom, the car has X joules of mechanical energy" is the one among the following choices given in the question that <span>the law of conservation of energy predict about the car. The correct option among all the options that are given in the question is the second option or option "B". I hope the answer helped you.</span>
The final momentum of the body is equal to 120 Kg.m/s.
<h3>What is momentum?</h3>
Momentum can be described as the multiplication of the mass and velocity of an object. Momentum is a vector quantity as it carries magnitude and direction.
If m is an object's mass and v is its velocity then the object's momentum p is:
. The S.I. unit of measurement of momentum is kg⋅m/s, which is equivalent to the N.s.
Given the initial momentum of the body = Pi = 20 Kg.m/s
The force acting on the body, Pf = 25 N
The time, Δt = 4-0 = 4s
The Force is equal to the change in momentum: F ×Δt = ΔP
25 × 4 = P - 20
100 = P - 20
P = 100 + 20 = 120 Kg.m/s
Therefore, the final momentum of a body is 120 Kg.m/s.
Learn more about momentum, here:
brainly.com/question/4956182
#SPJ1
In a longitudinal wave the particle displacement is parallel to the direction of wave propagation. ... The particles do not move down the tube with the wave; they simply oscillate back and forth about their individual equilibrium positions.Answer:
Explanation:
Newton's 2nd law of motion:
Net Force = (mass) x (acceleration) .
The law shows the relationship among an object's mass
and acceleration, and the net force acting on it.
If you know any two of the quantities in the formula,
the law can be used to calculate the third one.
Answer:
A) 1568.60 Hz
B) 1437.15 Hz
Explanation:
This change is frequency happens due to doppler effect
The Doppler effect is the change in frequency of a wave in relation to an observer who is moving relative to the wave source

where
C = the propagation speed of waves in the medium;
Vr= is the speed of the receiver relative to the medium,(added to C, if the receiver is moving towards the source, subtracted if the receiver is moving away from the source;
Vs= the speed of the source relative to the medium, added to C, if the source is moving away from the receiver, subtracted if the source is moving towards the receiver.
A) Here the Source is moving towards the receiver(C-Vs)
and the receiver is standing still (Vr=0) therefore the observed frequency should get higher

B)Here the Source is moving away the receiver(C+Vs)
and the receiver is still not moving (Vr=0) therefore the observed frequency should be lesser
