Answer:
a)
Explanation:
Given paraeters are:
R = 25 cm
d = 4.7 mm
f = 60 Hz
= 160 V
a)
Where Hz and V
For
Since
From Ampere's Law:
where
So at ,
For maximum B, cos(2πft) = 1. Hence,
T
b) From r = 0 to r = R = 0.025 m, by Ampere's Law, the equation will be:
From r = R = 0.025 m to r = 0.1 m, by Ampere's Law, the equation will be:
The plot is given in the attachment.
In order to accelerate the dragster at a speed
, its engine must do a work equal to the increase in kinetic energy of the dragster. Since it starts from rest, the initial kinetic energy is zero, so the work done by the engine to accelerate the dragster to 100 m/s is
however, we must take into account also the fact that there is a frictional force doing work against the dragster, and the work done by the frictional force is:
and the sign is negative because the frictional force acts against the direction of motion of the dragster.
This means that the total work done by the dragster engine is equal to the work done to accelerate the dragster plus the energy lost because of the frictional force, which is
:
So, the power delivered by the engine is the total work divided by the time, t=7.30 s:
And since 1 horsepower is equal to 746 W, we can rewrite the power as
It produces more infrared, which is a low-frequency invisible light.
Answer:
b) a horse pulls a wagon at a constant velocity
Explanation:
As we know that ,work done is the dot product of force vector and displacement vector.
W= F.d
W=work
F=Force
d=Displacement
We also know that
F = m a
m= mass ,a = acceleration
When velocity is constant then rate of change in the velocity will be zero,then we can say that acceleration will be zero.
When a= 0 Then F= 0
W= F.d ( F=0)
W = 0
Therefore option b i correct because horse is going with constant velocity.