Answer:
s = 20 m
Explanation:
given,
mass of the roller blader = 60 Kg
length = 10 m
inclines at = 30°
coefficient of friction = 0.25
using conservation of energy
u = 9.89 m/s
Using second law of motion
ma =μ mg
a = μ g
a = 0.25 x 9.8
a = 2.45 m/s²
Using third equation of motion ,
v² - u² = 2 a s
0² - 9.89² = 2 x 2.45 x s
s = 20 m
the distance moved before stopping is 20 m
Answer: a) 18670 W b) 25 hp
Explanation:
a)
Average power,
P = W/t
W= 0.5 MVf^2 - 0.5 MVo^2
Therefore P =( (0.5 x 112 x 34.5^2 ) - (0.5 x 112 x 0 ) ) / 3.57
P = 1.87 x 10^4 W
b)
Power in units of horsepower is
P = 1.87 x 10^4 / 745.7 = 25hp
If a tennis player does not swing through, meaning they stop swinging the moment they make contact with the ball, they would lose the majority of their power. <em>The momentum that they had built up during the swing is lost the moment they stop swinging</em>, meaning that the ball is hit with a low amount of power.
<em>If the tennis player swings through the whole time they hit the ball, then they keep their momentum as they hit the ball.</em> There is a much higher power level when swinging through than if you were to stop your swing when you hit the ball.
Answer:
450000 kg m/s
Explanation:
convert 108km/h to m/s
1km=100m
1h=(60×60)s = 3600s
108km/h= (108×1000)÷3600
=30m/s
K.E =1/2mv^2
=1/2(1×10^3)(30^2)
= 1/2 × 1000 × 900
= 450000 kg m/s
this should be your answer, hope I was able to help.
Changing the number of electrons changes the <em>net electric charge</em> of the atom.
If the atom was originally neutral, then it becomes an <em>ion</em> . (If it wasn't originally neutral, then it was already an ion.)