Answer:
792 J
Explanation:
The total energy of the ball is E = U + K where U = potential energy = mgh and K = kinetic energy = 1/2mv²
E = mgh + 1/2mv² where m = mass of ball = 2.0 kg, g = acceleration due to gravity = 9.8 m/s², h = height of building = 20.0 m, v = initial velocity of ball = 20.0 m/s.
So, substituting the values of the variables into E, we have
E = mgh + 1/2mv²
= 2.00 kg × 9.8 m/s² × 20.0 m + 1/2 × 2.00 kg × (20.0 m/s)²
= 392 J + 400 J
= 792 J
The change in velocity is 20 m/s to the north.
Answer:
Fm - W = 0 1) true. Imams must separate, to match the two forces, you reach equilibrium
Explanation:
When the magnet is exchanged for a stronger one, but of the same weight, the equilibrium equation
Fm - W = 0
Fm = W
If the weight of the imam is the same, the magnetite force must decrease, so that it will occupy the magnets must be separated a greater distance, according to the formula
Fm = Km m ’m / r²
Where Km is value 10⁻⁷ N s²/C², r is the distance between the poles
Let's review the proposed results
1) true. Imams must separate, to match the two forces, you reach equilibrium
2) False. In this case the weight would be less than the magnetic force
3) False The magnetic force increases and equilibrium is not reached
The reading will be 0.00. that is the least count<span> of </span>stopwatch<span>.</span>
