Answer:
2.26 s
Explanation:
The following data were obtained from the question:
Height (h) = 25 m
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) =..?
The time taken for the egg to hit the floor can be obtained as illustrated below:
h = ½gt²
25 = ½ × 9.8 × t²
25 = 4.9 × t²
Divide both side by 4.9
t² = 25 / 4.9
Take the square root of both side
t = √(25 / 4.9)
t = 2.26 s
Thus, it will take 2.26 s for the egg to hit the floor.
The answer is (A) the object must be at rest.
When all of the forces acting on an object balance, the net force is zero and hence the object will not move.
Yes, the direction might also change under some special circumstances.
Answer:
6.39 J of energy is needed to generate 0.71 * 10⁻¹⁶ kg mass
Explanation:
According to the Equation: E = mc²
where the mass, m = 0.71 * 10⁻¹⁶ kg
the speed of light, c = 3 * 10⁸ m/s
The amount of energy needed to generate a mass of 0.71 * 10⁻¹⁶ kg is calculated as follows:
E = (0.71 * 10⁻¹⁶) (3 * 10⁸)²
E = 0.71 * 10⁻¹⁶ * 9 * 10¹⁶
E = 0.71 * 9
E = 6.39 J
Answer:
A. -2.16 * 10^(-5) N
B. 9 * 10^(-7) N
Explanation:
Parameters given:
Distance between their centres, r = 0.3 m
Charge in first sphere, Q1 = 12 * 10^(-9) C
Charge in second sphere, Q2 = -18 * 10^(-9) C
A. Electrostatic force exerted on one sphere by the other is:
F = (k * Q1 * Q2) / r²
F = (9 * 10^9 * 12 * 10^(-9) * -18 * 10^(-9)) / 0.3²
F = -2.16 * 10^(-5) N
B. When they are brought in contact by a wire and are then in equilibrium, it means they have the same final charge. That means if we add the charges of both spheres and divided by two, we'll have the final charge of each sphere:
Q1 + Q2 = 12 * 10^(-9) + (-18 * 10^(-9))
= - 6 * 10^(-9) C
Dividing by two, we have that each sphere has a charge of -3 * 10^(-9) C
Hence the electrostatic force between them is:
F = [9 * 10^9 * (-3 * 10^(-9)) * (-3 * 10^(-9)] / 0.3²
F = 9 * 10^(-7) N
