·The acceleration of gravity is proportional to
1 / (the square of the distance from the center) .
When we're on the surface, we're 1 radius from the center of the Earth,
and the acceleration of gravity is 9.8 m/s² .
The boy's weight = (mass) · (gravity) = (50kg) · (9.8 m/s²)
= 490 newtons .
At the distance of 5 radii from the center (4 radii altitude from the surface),
the acceleration of gravity is
(9.8 m/s²) · (1/5)² = 0.39 m/s² .
The boy's weight is (mass) · (gravity) = (50kg) · (0.39 m/s²)
= 19.6 newtons .
Just as we expected, his weight at that distance is
(19.6 / 490) = 0.04 = 1/25 = 1/5² of his weight on the surface.
Answer:
Weight of the car, normal force, drag force
Explanation:
The forces acting on the car are:
- The normal force which acts perpendicularly to the downhill plane
- The weight of the car which acts vertically downwards
- The drag force due to air resistance which acts in opposition to the motion of the car
Friction is ignored, so the force due to friction is assumed negligible
I would say The answer is false
The letter u before any unit means micro. Micro is a unit
prefix used in the metric system which actually means a factor of 10^-6 (one
millionth).
Now, 10^-6 is equivalent to a movement of 6 decimal places
from left to right. So to write the number 0.0000078 s into a number which has
a unit of us, therefore we move the decimal place by 6 to the right, giving us:
7.8 us
Another way to do this is to multiply the number by 1
million (1,000,000), so:
0.0000078 * 1,000,000
Using the calculator to solve, we get the value:
7.8 us
The total mass of the galaxy is 443.4 Solar mass
Orbital velocity (
) = 
where M= weight of galaxy
G= gravitational constatnt =
(given)
R = distance from centre =
Light years (given)=
km (1 ly=
billion km)
v= orbital velocity =
(given)
∴ According to the formula
= 
⇒
(cross multiplying and expanding)
⇒ 
⇒ 
⇒ 
1 solar mass = 
⇒ Mass in solar mass =443.4 Solar mass
⇒ M = 443.4 Solar mass
Learn more about Orbital velocity here :
brainly.com/question/22247460
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