Answer:
Answered
Explanation:
A) The work done by gravity is zero because displacement and the gravitational force are perpendicular to each other.
W= FS cosθ
θ= 90 ⇒cos90 = 0 ⇒W= 0
B) work done by tension
W= Tcosθ×S= 5cos30×2.30= 10J
C) Work done by friction force
W= f×s=1×2.30= 2.30 J
D) Work done by normal force is Zero because the displacement and the normal force are perpendicular to each other.
E) The net work done= Work done by tension in the rope - frictional work
=10-2.30= 7.7 J
(a)
consider the motion of the tennis ball. lets assume the velocity of the tennis ball going towards the racket as positive and velocity of tennis ball going away from the racket as negative.
m = mass of the tennis ball = 60 g = 0.060 kg
v₀ = initial velocity of the tennis ball before being hit by racket = 20 m/s
v = final velocity of the tennis ball after being hit by racket = - 39 m/s
ΔP = change in momentum of the ball
change in momentum of the ball is given as
ΔP = m (v - v₀)
inserting the above values
ΔP = (0.060) (- 39 - 20)
ΔP = - 3.54 kgm/s
hence , magnitude of change in momentum : 3.54 kgm/s
Answer:
The sun
Explanation:
In this system the energy of the sun heats the water in the pipe, producing a high pressured steam, which is used for moving a turbine and producing electricity, is a transformation of energy from solar to thermal, then to mechanical to electrical.
Answer:
Explanation:
On the Moon :----
1500 x 1.6 = 2400 m /s is initial velocity of bullet .
g = 1.6 m /s²
v = u - gt
0 = 2400 - 1.6 t
t = 1500 s
This is time of ascent
Time of decent will also be the same
Total time of flight = 2 x 1500 = 3000 s
On the Earth : ---
v = u - a₁ t
0 = u - a₁ x 18
u = 18a₁
v² = u² - 2 x a₁ x 2743.2
0 = (18a₁ )² - 2 x a₁ x 2743.2
a₁ = 16.93
For downward return
s = ut + 1/2 a₂ x t²
2743.2 = 0 + .5 x a₂ x 31²
a₂ = 5.7 m /s²
If d be the deceleration produced by air
g + d = 16.93 ( during upward journey )
g - d = 5.7
g = (16.93 + 5.7) / 2
= 11.315 m / s
d = 5.6 m /s²
So air is creating a deceleration of 5.6 m /s².
