Answer:
a) W = 5360 J b) μ = 0.29
Explanation:
a) The work is, bold indicate vectors
W = F. d = F d cos T
W = 40 268 cos 60
W = 5360 J
b) The force of friction and opposes the movement of the body and if the speed of the body is constant implies that the external force in the direction of the movement is equal to the force of friction, or which work is the same
= -5360J
The negative sign is because the force of friction is contrary to the direction of movement
c) Let's write the work of the friction force
= fr d cos 180
fr = μ N
Since the body is on a horizontal surface, from Newton's second law on the Y axis
N-W = 0
N = W
fr = μ W
= - μ W d
μ = - / W d
μ = - (-5360) / 69 268
μ = 0.29
<span>None of the light passes through it; some of the light is absorbed as heat but most is reflected off the surface. This is how you see </span>objects. reflected light from them hits your eye. (Opaque means not transparent)
Answer:
630.75 j
Explanation:
from the question we have the following
total mass (m) = 54.5 kg
initial speed (Vi) = 1.4 m/s
final speed (Vf) = 6.6 m/s
frictional force (FF) = 41 N
height of slope (h) = 2.1 m
length of slope (d) = 12.4 m
acceleration due to gravity (g) = 9.8 m/s^2
work done (wd) = ?
- we can calculate the work done by the boy in pushing the chair using the law of law of conservation of energy
wd + mgh = (0.5 mVf^2) - (0.5 mVi^2) + (FF x d)
wd = (0.5 mVf^2) - (0.5 mVi^2) + (FF x d) - (mgh)
where wd = work done
m = mass
h = height
g = acceleration due to gravity
FF = frictional force
d = distance
Vf and Vi = final and initial velocity
wd = (0.5 x 54.5 x 6.9^2) - (0.5 x 54.5 x 1.4^2) + (41 x 12.4) - (54.5 X 9.8 X 2.1)
wd = 630.75 j
Answer:
The angular acceleration is 
Explanation:
From the question we are told that
The moment of inertia is 
The net torque is 
Generally the net torque is mathematically represented as
Where 
is the angular acceleration so
substituting values
Answer:
Explanation:
Considering non - relativistic approach : ----
Speed of electron = 1 % of speed of light
= .01 x 3 x 10⁸ m /s
= 3 x 10⁶ m /s
Kinetic energy of electron = 1/2 m v²
= .5 x 9.1 x 10⁻³¹ x ( 3 x 10⁶ )²
= 40.95 x 10⁻¹⁹ J
Kinetic energy in electron comes from lose of electrical energy equal to
Ve where V is potential difference under which electron is accelerated and e is electronic charge .
V x e = kinetic energy of electron
V x 1.6 x 10⁻¹⁹ = 40.95 x 10⁻¹⁹
V = 25.6 Volt .
