Answer:
He will complete the race in total time of T = 10 s
Explanation:
Total distance moved by the sprinter in 2.14 s is given as



now the distance remaining to move

now he will move with uniform maximum speed for the remaining distance
so we will have


so the total time to complete the race is given as

Answer:
Earth attract the Moon with a force that is greater.
Explanation:
According to the law of gravitation, the gravitational force between two masses is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
Mathematically, F1 = Gm1m2/r²... 1
Let m1 be the mass of the earth and m2 be that of the moon
If the Earth is much more massive than is the Moon, the new force of attraction between them will become;
F2= G(2m1)m2/r²
F2 = 2Gm1m2/r² ... (2)
Dividing eqn 1 by 2 we have;
F1/F2 = (Gm1m2/r²)÷(2Gm1m2/r²)
F1/F2 = Gm1m2/r²×r²/2Gm1m2
F1/F2 = 1/2
F2=2F1
This shows that that the earth will attract the moon by a force 2times the initial force of the masses(i.e a much greater force)
Answer:
5kgm
Explanation:
convert cm to m and g to kg
250/1000=0.25kg
5/1000=0.05m
then find the density
density=mass/volume
=0.25kg/0.05m
=5kgm
Answer:
a.Distance = 150 m
b. Displacement = 50 m
Time lapsed = 5 seconds
Explanation:
a. Distance is the change in the position of an object.
The distance covered by the car = 100 + 50
= 150 m
b. Since displacement is a vector quantity,
Displacement of the car = 100 - 50
= 50 m due east
c. Time elapsed is the time taken for the motion of the car starting from when its starts to when it stops.
Thus, the time elapsed = 4 + 1
= 5 seconds
Using V= vo +at with Vo = 0 and a= 4m/sec2.
V= 0+ 4x8= 32m/s