Answer:
628.022466 N
8.61 m/s
Explanation:
m = Mass
= Coefficient of friction
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration
g = Acceleration due to gravity = 9.81 m/s²

Magnitude of frictional force is 628.022466 N


Initial speed of the player is 8.61 m/s
Answer:
1.2cm
Explanation:
V=(2ev/m)^1/2
=(2*1.6*10^19 x2500/ 1.67*10^27)^1/2
=6.2x10^5m/s
Radius of resulting path= MV/qB
= 1.67*10^-27x6.92*10^6/1.6*10^-16 x0.6
=0.012m
=1.2cm
Answer:
Stretch can be obtained using the Elastic potential energy formula.
The expression to find the stretch (x) is 
Explanation:
Given:
Elastic potential energy (EPE) of the spring mass system and the spring constant (k) are given.
To find: Elongation in the spring (x).
We can find the elongation or stretch of the spring using the formula for Elastic Potential Energy (EPE).
The formula to find EPE is given as:

Rewriting the above expression in terms of 'x', we get:

Example:
If EPE = 100 J and spring constant, k = 2 N/m.
Elongation or stretch is given as:

Therefore, the stretch in the spring is 10 m.
So, stretch in the spring can be calculated using the formula for Elastic Potential Energy.
Answer:
The velocity of the freight car decreases.
Explanation:
This question is answered by the conservation of momentum principle.
When the freight car is moving at a certain speed, it has a constant momentum.
We will call this M1.
The equation for M1 will be:
M1 = Mass * Speed
Now when the coal is dumped into the freight car, the Mass increases.
Since conservation of momentum states that the momentum will remain the same. We have:
M1 = (Mass of freight + Mass of coal) * Speed
Since M1 is constant, if the mass increases, the speed had to decrease to keep the equation true.
Answer: Some conversions from one system of units to another need to be exact, without increasing or decreasing the precision of the first measurement. This is sometimes called soft conversion. It does not involve changing the physical configuration of the item being measured.
Explanation: