Answer:

Explanation:
The interaction of the piece of copper and water means that the first one need to transfer heat in order to reach a thermal equilibrium with water. Then:

After a quick substitution, the expanded expression is:



The final temperature of the system is:

Answer:
537 N
Explanation:
The force due to gravity of a planet is:
F = GMm / r²
where G is the universal gravitational constant
M is the mass of the planet
m is the mass of the object
and r is the distance between the object and the center of the planet
On Earth, you weigh 716 N, so:
716 N = GMm / r²
On planet X:
F = G (3M) m / (2r)²
F = 3/4 GMm / r²
F = 3/4 (716 N)
F = 537 N
Answer:
Final velocity of the car will be -9.28 m/sec
Explanation:
We have given that the car starts from the rest so initial velocity of the car u = 0 m /sec
Acceleration of the car
in negative direction so acceleration will be 
From first equation of motion we know that
v = u+at
So 
So final velocity will be -9.28 m/sec
The mechanical advantage is the factor by which
the machine multiplies the input force.
If the MA is 3 and the input force is 630N, then
the output force is
(3) x (630N) = 1,890N
Answer: C
Explanation: Side post terminals need to be removed to inspect them for corrosion.
Over tightening the terminal bolt can damage side post terminals.
The battery terminals and cable ends can corrode especially when the battery or car is not used for a long period of time. Corrosion limits a battery's lifespan and so should be prevented. To inspect the areas where corrosion occur on a side-post battery, you need to remove the terminals.
Also, it is true that over tightening the terminal bolt can damage the side post terminals. The covering on the battery can become twisted, and make the seals on the terminals leak.