Answer:
Option D: Four times the original speed.
Explanation:
A centripetal force accelerates a body by changing the direction of the body's velocity without changing the body's speed.
The speed(v) is therefore constant, thereby making the magnitudes of the of the acceleration and the force constant.
The formula used to calculate the Centripetal force is given below:

where F represents the Centripetal force, m represents the mass of the moving body, v represents the speed or velocity at which the body is moving and r represents the radius.
Making the speed the subject of the formula: 
Therefore, when the radius (r) is changed to 4r, i.e r = 4r
speed(v) becomes 
After comparing, the difference between the speeds is Four times the original speed.
Answer:
A. It makes astronauts weightless.
Explanation:
Gravity does not make astronauts feel weightless. Astronauts are weightless because they are orbiting at the same rate as their shuttle.
Although the force of gravity weakens as one moves away from the earth surface, it does not mean that this force is absent in orbit
- Gravitational force has a constant acceleration value near the earth surface which is commonly known to be 9.8m/s².
- It is a force of attraction tending to hold and bind bodies together so far they have mass.
- This force keeps every thing from escaping space-ward from the earth surface.
First the plane turns 100 km North, and than 200 km East. Since both the directions are perpendicular to each other, therefore we can apply the Pythagoras theorem to calculate the distance between the destination and the point where plane took off
=100^{2}+200^{2}
D=223.60 km=224 km
Therefore, The destination is 224 km from where the plane took off
Answer:
V = 192 kV
Explanation:
Given that,
Charge, 
Distance, r = 0.3 m
We need to find the electric potential at a distance of 0.3 m from a point charge. The formula for electric potential is given by :

So, the required electric potential is 192 kV.
Keep cool by being active at night, whereas some other desert animals get away from the sun's heat by digging underground burrows.