Answer:82. Since you have a distance and a force, then the easiest principle to use is energy, i.e. work.
The work done by friction is F * d. This work cancels out the kinetic energy of the stone (1/2)mv^2
Fd = (1/2)mv^2
F = (1/2)mv^2/d.
Plug in m = 20 kg, v = 3 m/sec, d = 40 m.
83. With more mass, the kinetic energy is higher now. The work needed is higher. W = F * d and F is the same.
Explanation:Hope I helped :)
Explanation:
The given data is as follows.
q = 6.0 nC =
inner radius (r) = 1.0 cm = 0.01 m (as 1 cm = 100 m)
So, there will be same charge on the inner surface as the charge enclosed with an opposite sign.
Formula to calculate the charge density is as follows.
.......... (1)
Since, area of the sphere is as follows.
A = ........... (2)
Hence, substituting equation (2) in equation (1) as follows.
=
=
or, = 4.77
Thus, we can conclude that the resulting charge density on the inner surface of the conducting sphere is 4.77 .
Answer:
The speed of the rain is
Explanation:
From the question we are told that
The initial speed and direction of the car is
The angle made with the horizontal is
The velocity of rain is
An illustrate of this question is shown on the first uploaded image
From the diagram we see that
=>
substituting values
Answer:
(a) 2800 J
(b) 31.28 %
Explanation:
Heat intake, Q1 = 8950 J
Heat discard, Q2 = 6150 J
(a) Work = intake heat energy - discarded heat energy
W = Q1 - Q2 = 8950 - 6150 = 2800 J
(b) Efficiency = 1 - Q2 / Q1
Efficiency = 1 - (6150 / 8950) = 0.3128 = 31.28%
Answer:
α = 0.0135 rad/s²
Explanation:
given,
t = 133 min = 133 x 60 = 7980 s
angular speed varies from 570 rpm to 1600 rpm
now,
570 rpm =
= 59.69 rad/s
1600 rpm = =
= 167.6 rad/s
using equation of rotational motion
ωf = ωi + αt
167.6 = 59.7 + α x 7980
α x 7980 = 107.9
α = 0.0135 rad/s²