Answer:
All the competitors will move with the same velocity.
Explanation:
Here, the situations for each competitor are identical. Thus, they will exert the same force and hence, their velocities at each instants will be identical.
Answer:
a) 3-in. pipe
Explanation:
Given that
Fluid flow is in same amount in the same time it means that volume flow rate is same for the pipes
Volume flow rate
Q = A V
A=Area ,V=Velocity

If diameter d is more then the velocity will be less for same volume flow rate .We also Know that if pressure is more then the velocity will be less.
The second pipe 3 in diameter having more diameter then the velocity will be less but the pressure will be more.
That is why the 3 in diameter is having more pressure than 2 in diameter pipe.
Therefore the answer will be a.
a) 3-in diameter pipe
Answer: Physical
Explanation: There are no changes being done to the salt. Think of it this way, if you dissolve the salt in water then boil the water completely, you will have the same salt you started with.
Answer:
i don't understand the hw
Explanation:
see, torque=force × perpendicular distance
...that perpendicular distance is between axis of rotation and the point where force acts... so in above's case perpendicular distance is zero... so the torque is zero!