Answer:
3.59 m/s
Explanation:
We are given that
Mass of lineman,m=85 kg
Mass of receiver,m'=90 kg
Speed of receiver,v'=5.8 m/s
Speed of lineman,v=4.1 m/s

We have to find the their velocity immediately after the tackle.
Initial momentum,
According to law of conservation of momentum
Initial momentum=Final momentum=


The power developed is 500 W ( to the nearest Watt)
Power(P) is the rate at which work is done. Work done (W) is the product of the force applied on the object and the displacement (s) made by the point of application of the force.


Therefore,

Substitute the given values of force , displacement and time


Thus the Power can be rounded off to the nearest value of 500 W
The last one is correct (D)
Answer:
E=
Explanation:
We are given that
Charge on ring= Q
Radius of ring=a
We have to find the magnitude of electric filed on the axis at distance a from the ring's center.
We know that the electric field at distance x from the center of ring of radius R is given by

Substitute x=a and R=a
Then, we get




Where K=
Hence, the magnitude of the electric filed due to charged ring on the axis of ring at distance a from the ring's center=
Density = Mass divided by Volume