Answer:
Explanation:
A )
speed of swimming in still water is given by the expression
distance / time
= 50 / 25
= 2 m /s
In lane 1 , 1.2 cm/s current is flowing in the direction that the swimmers are going so swimmers will cover distance at the rate of 2 + 1.2 = 3.2 m /s.
time to cover distance of 50 m in lane 1
= distance / speed
= 50 / 3.2 = 15.625 s
In lane 8 , 1.2 cm/s current is flowing against the direction that the swimmers are going so swimmers will cover distance at the rate of 2 - 1.2 = .8 m /s.
time to cover distance of 50 m in lane 1
= distance / speed
= 50 / .8 = 62.5 s
Balanced. They’re equally as strong so as their arm wrestling, neither of the men’s hands go down. Because they’re equally/balanced as strong.
Answer:
Part a)

Direction of force is along the motion of charge
Part b)

direction of electric field is along the direction of motion
Explanation:
Part a)
As we know that the change in electric potential energy is equal to the work done by electric field


now from the equation of work done we know that



Direction of force is along the motion of charge
Part b)
As we know the relation between electrostatic force and electric field given as



direction of electric field is along the direction of motion
Answer:

Explanation:
q = Charge of proton = 
v = Velocity of proton = 
c = Speed of light = 
B = Magnetic field = 0.00687 T
= Angle = 
Magnetic force is given by

The magnetic force acting on the proton is 
Answer:
9000RPM
Explanation:
"Angular velocity" is directly related to kinetic energy, that is, the Kinetic energy equation would allow an approximation to the resolution investigated in the problem.
The equation for KE is given by:

Now, starting from there towards the <em>Angular equation of kinetic energy</em>, the moment of inertia (i) is used instead of mass (m), and angular velocity (w) instead of linear velocity (V)
That's how we get

calculating the inertia for a solid cylindrical disk, of
m = 400kg
r = 1.2 / 2 = 0.6m

We understand that the total kinetic energy is 3.2 * 10 ^ 7J, like this:



Thus,
943 rad / s ≈ 9000 rpm