Answer:
remove contamination; pollution ; test ground water and dirt .
Answer:
41.3 m/s^2 option (e)
Explanation:
force, F = 6.81 N
mass, m = 165 g = 0.165 kg
Let a be the acceleration of the puck.
Use newtons' second law
Force = mass x acceleration
6.81 = 0.165 x a
a = 41.27 m/s^2
a = 41.3 m/s^2
Thus, the acceleration of the puck is 41.3 m/s^2.
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
The atomic number is the number of protons. So, you can subtract the atomic number from the mass number to find the number of neutrons.
I hope this helps! :)