Assuming it is on a horizontal surface:
friction = μR
R = 20g (g is gravity 9.81)
so Friction = 0.085 x 20g
Work done is force x distance
so Work done = 0.085 x 20g x 28
= 466.956 J
It is given that an<span> airplane is flying through a thundercloud at a height of 2000 m.
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Since the parity of charges is opposite and the airplane lies between the two charges and both the electric fields are in the same direction at the plane. Therefore, the magnitudes of the electric field at the aircrafts will add up.
Now, check the image to see the calculations:
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Answer:
1.7 seconds
Explanation:
To clear the intersection, the total distance to be covered = 59.7 + 25 =84.7m
first we need to find the initial speed to just enter the intersection by using the third equation of motion
v^2 - u^2 = 2*a*s
45^2 - u^2 = 2 * -5.7 * 84.7
u^2 = 45^2 +965.58
u^2 = 2990.58
u = 54.7 m/s
Now for time we apply the first equation of motion
v-u =a * t
t = (v-u)/a = (45 - 54.7)/-5.7 = 1.7seconds
-- Toss a rock straight up. The kinetic energy you give it
with your hand becomes potential energy as it rises.
Eventually, when its kinetic energy is completely changed
to potential energy, it stops rising.
-- When you're riding your bike and going really fast, you come
to the bottom of a hill. You stop pedaling, and coast up the hill.
As your kinetic energy changes to potential energy, you coast
slower and slower. Eventually, your energy is all potential, and
you stop coasting.
-- A little kid on a swing at the park. The swing is going really fast
at the bottom of the arc, and then it starts rising. As it rises, the
kinetic energy changes into potential energy, more and more as it
swings higher and higher. Eventually it reaches a point where its
energy is all potential; then it stops rising, and begins falling again.
A star chart<span> or </span>star map<span> is a </span>map<span> of the night </span>sky <span>Astronomers divide these into grids to use them more easil They are used to identify and locate astronomical objects such as stars constellations and galaxie it is in my text book </span>