Answer:
a. The speed is 2.39 m/s
b. The acceleration of the block is 10.2
Explanation:
First, we have to do the energy balance where we consider two states, the first where the spring remains still and the second when it is stretched 0.400m:
Δx=
W_{ext}=20.4 Nm
To determine, the acceleration we solve the following equation for a:
Velocity of wave= wavelength/wave period;
i.e., 100/20=5 meter/sec
Answer:
False
Explanation:
If a point charge has electric field lines point into it,then charge must be negative because electric lines point into negative charges and point out of positive charges
The watts determine the brightness. Watt is the unit of Power. And Power is equal to Voltage x Amps (current). So both the current and voltage determine the brightness.
Answer:
a) 5 N b) 225 N c) 5 N
Explanation:
a) Per Coulomb's Law the repulsive force between 2 equal sign charges, is directly proportional to the product of the charges, and inversely proportional to the square of the distance between them, acting along the line that joins the charges, as follows:
F₁₂ = K Q₁ Q₂ / r₁₂²
So, if we make Q1 = Q1/5, the net effect will be to reduce the force in the same factor, i.e. F₁₂ = 25 N / 5 = 5 N
b) If we reduce the distance, from r, to r/3, as the factor is squared, the net effect will be to increase the force in a factor equal to 3² = 9.
So, we will have F₁₂ = 9. 25 N = 225 N
c) If we make Q2 = 5Q2, the force would be increased 5 times, but if at the same , we increase the distance 5 times, as the factor is squared, the net factor will be 5/25 = 1/5, so we will have:
F₁₂ = 25 N .1/5 = 5 N
