Explanation:
Work done is the force applied to move a body through a specific or particular direction.
It is also the difference in the amount of energy expended in using an effort.
Work done is given as;
Work done = F x d CosФ
F is the force applied
d is the displacement
Ф is the angle
The unit of work done is in Joules.
Explanation:
A train moves at a high velocity. Velocity is the rate of motion, speed or action. An example of velocity is a car driving at 75 miles per hour.
Answer:
Power = 30 [watts]
Explanation:
Initia data:
F = force = 30[N]
d = displacement = 2 [m]
By definition we know that work is equal to the product of force by the distance displaced
Therefore:
W = F * d = 30 * 2
W = 60 [J]
And power is defined as the amount of work done in a given time interval
time = t = 2 [sec]
Power = W / t
Power = 60 / 2
Power = 30 [W]
Answer:
a. 0.275m/s
b. 1.08m
Explanation:
Since the duck the paddle the water at an interval of 1.6sec, we can determine the frequency of the wave formed using the equation
f=1/T
Where T is the period.
f=1/1.6
f=0.625Hz.
Also from the equation used in determining the speed of a wave
V=fλ,
v=0.625*0.2
v=0.125m/s
in the question it was stated that that the duck produce a wave moving at a speed of 0.40m/s.
Hence the speed of the duck is
v(duck)=0.40-0.125
v(duck)=0.275m/s
b. The distance between the crest behind the duck is the wavelength of the waves.
To determine this, the wavelength is expressed as
λ=v/f
but the speed in this case is the speed of the duck and the surface wave,as this account for the wave speed behind the duck,
Hence we have
λ=(0.40+0.275)/0.625
λ=1.08m.
The wavelength behind the duck is 1.08m
