Answer:
option A
Explanation:
given,
height of the drop of stone = 9.44 m
speed of the stone = ?
As the stone is dropped the energy of the stone will be conserved.
using conservation of energy.
Potential energy = Kinetic energy

v = 13.60 m/s
Hence, the correct answer is option A
Answer:
b) 338 N
Explanation: let m be the mass of the gymnast and a be the acceleration of the gymnast.
the force required to accelerate the gymnast is given by:
F = m×a
= (45.0)×(7.50)
= 337.5 N
Therefore, the force a trampoline has to apply is 138 N.
Answer:
Maximum Tension=224N
Minimum tension= 64N
Explanation:
Given
mass =8 kg
constant speed = 6m/s .
g=10m/s^2
Maximum Tension= [(mv^2/ r) + (mg)]
Minimum tension= [(mv^2/ r) - (mg)]
Then substitute the values,
Maximum Tension= [8 × 6^2)/2 +(8×9.8)] = 224N
Minimum tension= [8 × 6^2)/2 -(8×9.8)]
=64N
Hence, Minimum tension and maximum Tension are =64N and 2224N respectively
The time required for a moon to orbit around the earth is about 27-28 days
In order for lunar eclipse to occur the line that should be formed is:
Sun-Earth-Moon
because earth is making shade on moon
in order for solar eclipse to occur the line is now:
Sun-Moon-Earth
because moon is making a shade on earth (blocking sun = solar eclipse)
Therefore moon needs to make half of its orbit to go from behind the earth to in front of the earth.
28/2 = 14
Answer is 14