Answer:
0.6983 m/s
Explanation:
k = spring constant of the spring = 0.4 N/m
L₀ = Initial length = 11 cm = 0.11 m
L = Final length = 27 cm = 0.27 m
x = stretch in the spring = L - L₀ = 0.27 - 0.11 = 0.16 m
m = mass of the mass attached = 0.021 kg
v = speed of the mass
Using conservation of energy
Kinetic energy of mass = Spring potential energy
(0.5) m v² = (0.5) k x²
m v² = k x²
(0.021) v² = (0.4) (0.16)²
v = 0.6983 m/s
At the hightest point it would be potential energy, because the energy is stored and then when it is rocking back and forth it has kinetic energy
Answer:
1.6×10⁻⁶ N.
Explanation:
From the question,
F = (V/r)q......................... Equation 1
Where F = Electric force on the raindrop, V = Potential difference between the base of the cloud and the ground, r = distance between the base of the cloud and the ground, q = the charge on a rain drop.
Given: V = 200MV = 200×10⁶ V, r = 500 m, q = 4.0×10⁻¹² C.
Substitute these values into equation 1
F = [(200×10⁶ )/500]×4.0×10⁻¹²
F = 1.6×10⁻⁶ N.
<span>To calculate the density, we must first calculate the volume of the object. For a rectangle, the volume is equal to V=l*w*h. In this case, V=22*13.5*12.5=3712.5 mm^3. Next we have to convert the mm^3 to mL using the conversion factor of 1 mm^3=.001 mL. To get mL, we set up the expression 3712.5 mm^3 * (.001mL/1mm^3) = 3.7125 mL. Finally, to get the density, we know density is mass over volume, so we set the expression p=m/V=2.5g/3.7125mL=.6734 which rounded to 3 significant figures is .673. The answer will be .673</span>
Answer:
120 volts is the root mean square (rms) average of the voltage as it varies with time.
Explanation:
A. The average voltage over many weeks of time (false)
Reason: Average AC voltage over one cycle is cycle (from one peak to other) is zero and so over many weeks of time it is zero.
B. The peak voltage from an AC wall receptacle (false)
Reason: The peak voltage of an AC source in North America is zero.
C. The arithmetic mean of the voltage as it varies with time (false)
Reason: Arithmetic mean AC voltage over one cycle is cycle (from one peak to other) is zero and so over many weeks of time it is zero.
D. One-half the peak voltage (false)
Peak voltage =170 Volts
One-half the peak voltage = 85 volts
E. The root mean square (rms) average of the voltage as it varies with time (True)
Reason:
The peak voltage and root mean square voltage are related by:

Average value of voltage over one cycle is zero, so instead of calculating average voltage for AC peak voltage is first squared and the mean is calculated.