Answer:
<h2>5.6kW</h2>
Explanation:
Step one:
given
mass m= 24kg
distance moved= 6m
time taken= 4seconds
Step two:
Required
power
but work done is the force applied at a distance, and the power is the work done time the time taken
Work done= F*D
F=mg
W= mg*D
W=24*9.81*6
W=1412.6J
Power P= work * time
P=1412.6*4
p=5650.5W
P=5.6kW
The turns ratio is the factor that determines voltage andcurrent. In order to have the same current across the resistorin the primary as the resistor in the secondary, then:--N(p) = Primary turnsN(s) = Secondary turnsR(2) = Primary resistorR(1) = Secondary resistor--R(2)/R(1) = N(p)/N(s)R(2) = R(1)*(N(p)/N(s))--If arbitrary values are plugged in, you will see that this step up transformer will require 2x the resistance required in the secondary, R(1), to obtain the same current. Thus R(2) will be 1/2 the value of R(1). This is due to the stepped up voltage in the secondary.
Answer:
50.0543248872 ft
Explanation:
F = Load = 20 ton = 
d = Diameter = 1.25 in
= Initial length = 50 ft
= Final length
A = Area = 
Y = Young's modulus = 
Young's modulus is given by

The length during the lift is 50.0543248872 ft
Answer:
Emitted power will be equal to 
Explanation:
It is given factory whistle can be heard up to a distance of R=2.5 km = 2500 m
Threshold of human hearing 
We have to find the emitted power
Emitted power is equal to 


So emitted power will be equal to 
Answer:
3.28 m
3.28 s
Explanation:
We can adopt a system of reference with an axis along the incline, the origin being at the position of the girl and the positive X axis going up slope.
Then we know that the ball is subject to a constant acceleration of 0.25*g (2.45 m/s^2) pointing down slope. Since the acceleration is constant we can use the equation for constant acceleration:
X(t) = X0 + V0 * t + 1/2 * a * t^2
X0 = 0
V0 = 4 m/s
a = -2.45 m/s^2 (because the acceleration is down slope)
Then:
X(t) = 4*t - 1.22*t^2
And the equation for speed is:
V(t) = V0 + a * t
V(t) = 4 - 2.45 * t
If we equate this to zero we can find the moment where it stops and begins rolling down, that will be the highest point:
0 = 4 - 2.45 * t
4 = 2.45 * t
t = 1.63 s
Replacing that time on the position equation:
X(1.63) = 4 * 1.63 - 1.22 * 1.63^2 = 3.28 m
To find the time it will take to return we equate the position equation to zero:
0 = 4 * t - 1.22 * t^2
Since this is a quadratic equation it will have to answers, one will be the moment the ball was released (t = 0), the other will eb the moment when it returns:
0 = t * (4 - 1.22*t)
t1 = 0
0 = 4 - 1.22*t2
1.22 * t2 = 4
t2 = 3.28 s