What are laws of newton
2 answers:
You might be interested in
Answer:
The gravitational force is definitely acting downwards towards the ground and this is equal to the weight of the skydiver.
the acceleration a = 7.8 m/s²
Explanation:
Given that :
the mass of the skydiver = 60 kg
Velocity = 50 m/s
Thus; gravitational force is definitely acting downwards towards the ground and this is equal to the weight of the skydiver.
Also; the air resistance is acting upward and the resultant of both forces = mass×acceleration
So;
mg-R = ma
60(9.8) - 120 = 60(a)
588 -120 = 60a
468 = 60a
a =
a = 7.8 m/s²
Hence, the acceleration a = 7.8 m/s²
The kinetic energy of the object just after it starts its motion from the Earth surface is
where m is the object mass and
its initial speed.
When it reaches its maximum height, the object speed is zero and all its kinetic energy converted into gravitational potential energy, which is
where
and h is the maximum height reached by the object.
Since the energy of the object must be conserved, K=U, therefore we can write
and we can solve to find h, the maximum height:
where m is the object mass and
When it reaches its maximum height, the object speed is zero and all its kinetic energy converted into gravitational potential energy, which is
where
Since the energy of the object must be conserved, K=U, therefore we can write
and we can solve to find h, the maximum height: