Answer:
Option (b) is correct.
Explanation:
The motion under the influence of gravity is called projectile motion.
The acceleration due to gravity is constant through out the motion and it is always acting downwards.
When an athlete jumps and follow the projectile path, it always have the same horizontal velocity as there is no acceleration in the horizontal direction.
Also he has the vertical acceleration constant which is equal to the acceleration due to gravity and acts towards the center of earth.
Option (b) is correct.
Answer:71 dB
Explanation:
Given
sound Level 
distance 
From sound Intensity





we know Intensity 




Sound level corresponding to 



Answer:
660 centimeters
Explanation:
There are 100 cm in 1 m. To convert from m to cm, multiply by 100.

There are 660 cm in 1 m.
So first, we multiply mass by gravity by height, which is 60 * 9.8 * 74.8 = <span>43747.2
So the answer is: </span><span>
43747.2Hope this helped! c:</span>
In the above problem, we need to find mass of the second child, so that the Center of Mass remains at the origin( pivot).
CM= m1r1+m2r2/m1+m2
0= 20*-2+16*r2/20+16
r2= 40/16
r2= +2.5 m