Actually, they're not. There's a group of stars and constellations arranged
around the pole of the sky that's visible at any time of any dark, clear night,
all year around. And any star or constellation in the rest of the sky is visible
for roughly 11 out of every 12 months ... at SOME time of the night.
Constellations appear to change drastically from one season to the next,
and even from one month to the next, only if you do your stargazing around
the same time every night.
Why does the night sky change at various times of the year ? Here's how to
think about it:
The Earth spins once a day. You spin along with the Earth, and your clock is
built to follow the sun . "Noon" is the time when the sun is directly over your
head, and "Midnight" is the time when the sun is directly beneath your feet.
Let's say that you go out and look at the stars tonight at midnight, when you're
facing directly away from the sun.
In 6 months from now, when you and the Earth are halfway around on the other
side of the sun, where are those same stars ? Now they're straight in the
direction of the sun. So they're directly overhead at Noon, not at Midnight.
THAT's why stars and constellations appear to be in a different part of the sky,
at the same time of night on different dates.
If we neglet air resistance for both objects then both will fall parallely(at same time) because time taken by both objects is independent of mass. there is famous experiment i.e"feather coin experiment" . normally we think that heaver objects falls faster but this is wrong concept. it depends on medium in which objects are moving.
thanku
The work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.
<h3>What is normal force?</h3>
The force of contact is called the normal force. When the two surfaces are in contact with each other, then the normal force acts.
This force is applied by the solid bodies on each other in order to prevent the passing through each other.
A box slides down a frictionless incline, gaining speed. For this box, the value of work done by normal force has to be found out. Let's analyze the given condition.
- The body is gaining the speed, which means there is a change in kinetic energy.
- The change in kinetic energy is equal to the work done.
- The friction force is the product of coefficient of the friction and normal force.
- The friction force for the given case is zero. Thus, the normal force must be equal to the zero.
Thus, the work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.
Learn more about the normal force here;
brainly.com/question/10941832
A 16.0 kg crate increases in height from 1.80 m to 3.30 m above the floor. The increase in potential energy is 240 J (a).
<h3>What is potential energy?</h3>
It is the energy due to the position.
A 16.0 kg (m) crate rests on a shelf 1.80 m (h₁) above the floor in a warehouse. The potential energy is:
U₁ = m × g × h₁ = 16.0 kg × (9.81 m/s²) × 1.80 m = 283 J
A forklift is used to raise the crate to a shelf 3.30 m (h₂) above the warehouse floor. The potential energy is:
U₂ = m × g × h₂ = 16.0 kg × (9.81 m/s²) × 3.30 m = 518 J
The increase in the potential energy is:
518 J - 283 J = 235 J ≈ 240 J
A 16.0 kg crate increases in height from 1.80 m to 3.30 m above the floor. The increase in potential energy is 240 J (a).
Learn more about potential energy here: brainly.com/question/23979653
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Answer:
correct answer is narrow
Explanation:
solution
when we pass someone riding bicycle ahead you then we should decrease our speed and increase the distance between you and bicyclist
and we should ride on road with very predictable manner and we should ride in straight line and if If road is too narrow for a bicycle
then we should ride vehicle to travel side by side so bicyclist should occupy lane until it safe
so here correct option is narrow
