Answer: Part(a)=0.041 secs, Part(b)=0.041 secs
Explanation: Firstly we assume that only the gravitational acceleration is acting on the basket ball player i.e. there is no air friction
now we know that
a=-9.81 m/s^2 ( negative because it is pulling the player downwards)
we also know that
s=76 cm= 0.76 m ( maximum s)
using kinetic equation

where v is final velocity which is zero at max height and u is it initial
hence


now we can find time in the 15 cm ascent


using quadratic formula

t=0.0409 sec
the answer for the part b will be the same
To find the answer for the part b we can find the velocity at 15 cm height similarly using

where s=0.76-0.15
as the player has traveled the above distance to reach 15cm to the bottom


when the player reaches the bottom it has the same velocity with which it started which is 3.861
hence the time required to reach the bottom 15cm is

t=0.0409
Answer:

Explanation:
Given that,
The mass of a golf ball, m = 40 g = 0.04 kg
Its angular velocity, 
The radius of the sphere is 2.5 cm or 0.025 m
We need to find the magnitude of the angular momentum of the ball. It is given by the formula as follows:

Where I is moment of inertia
For sphere, 

So, the magnitude of the angular momentum of the sphere is
.
The car should have a velocity of 60 m/s to attain the same momentum as that of the truck of 2000 kg.
Answer:
Explanation:
Momentum is measured as the product of mass of object with the velocity attained by that object.
Momentum of 2000 kg truck = Mass × Velocity
Momentum of 2000 kg truck = 2000×30 = 60000 N
Similarly, the momentum of 1000 kg car will be 1000× velocity of the 1000 kg car.
Since, it is stated that momentum of 2000 kg truck is equal to the momentum of 1000 kg of car, then the velocity of 1000 kg of car can be determined by equating the momentum of car and truck.
Momentum of 2000 kg truck = Momentum of 1000 kg car
60000=1000×velocity of 1000 kg car
Velocity of 1000 kg car = 60000/1000=60 m/s
So, the car should have a velocity of 60 m/s to attain the same momentum as that of the truck of 2000 kg.