Answer:
<h2>50 J</h2>
Explanation:
The work done by an object can be found by using the formula
workdone = force × distance
From the question
force = 25 N
distance = 2 m
We have
workdone = 25 × 2 = 50
We have the final answer as
<h3>50 J</h3>
Hope this helps you
Answer:
a. 120 W
b. 28.8 N
Explanation:
To a good approximate, the only external force that does work on a cyclist moving on level ground is the force of air resistance. Suppose a cyclist is traveling at 15 km/h on level ground. Assume he is using 480 W of metabolic power.
a. Estimate the amount of power he uses for forward motion.
b. How much force must he exert to overcome the force of air resistance?
(a)
He is 25% efficient, therefore the cyclist will be expending 25% of his power to drive the bicycle forward
Power = efficiency X metabolic power
= 0.25 X 480
= 120 W
(b)
power if force times the velocity
P = Fv
convert 15 km/h to m/s
v = 15 kmph = 4.166 m/s
F = P/v
= 120/4.166
= 28.8 N
definition of terms
power is the rate at which work is done
force is that which changes a body's state of rest or uniform motion in a straight line
velocity is the change in displacement per unit time.
Given data:
* The extension of the steel wire is 0.3 mm.
* The length of the wire is 4 m.
* The area of cross section of wire is,

* The young modulus of the steel is,

Solution:
The young modulus of the steel in terms of the force and extension is,

where F is the force acting on the steel wire,, l is the original length of the wire, dl is the extension of the wire, and A is the area,
Substituting the known values,

Thus, the force which produce the extension of 0.3 mm of the steel wire is 31.5 N.
Answer:
Explanation:
fringe separation or fringe width is directly proportional to wavelength .
Δ₁ / Δ₂ = wave length of first laser / wavelength of second laser
Δ₁ is fringe separation in first case and Δ₂ is fringe separation in second case.
putting the given values
632.8 / wavelength of second laser = 4.5 / 4.64
wavelength of second laser = 632.8 x (4.64 / 4.5)
= 652.48 nm
652 nm
Answer:
The inductance of this solenoid is 5.51 mH.
Explanation:
Given that,
length of the tube, l = 38 cm = 0.38 m
Diameter of the tube, d = 8.3 cm
Radius of the tube, r = 4.15 cm
The number of turns, N = 555
We need to find the inductance of this solenoid. It is given by the formula as :

So, the inductance of this solenoid is 5.51 mH. Hence, this is the required solution.