Both valves are closed during the power stroke.
While the fuel is burning in the cylinder, you want
all the force of the expanding gases to push the
piston down ... you don't want any of the gases
or their pressure escaping.
If either of the valves was open, even just a crack,
then part of the gases would go blooey out the valve,
and some pressure would be lost that's supposed to be
pushing the piston.
Answer:
Sun heating a car sitting in a parking lot
Explanation:
The sun heating a car sitting in a parking lot is an example of electromagnetic waves transferring energy.
- Electromagnetic waves are produced from the vibration between electric and magnetic fields.
- These waves can be propagated through vacuum with no particles inside of them.
- The sun produces electromagnetic radiation through the process of nuclear fusion.
- These radiations are used to warm the earth surface.
- The sun heating a car sitting a parking lot is one vivid example.
Answer:
reflection of water ,sound and water waves etc
Answer: 39.8 μC
Explanation:
The magnitude of the electric field generated by a capacitor is given by:
d is the distance between the plates.
For a capacitor, charge Q = CV where C is the capacitance and V is the voltage.
where A is the area of the plate and ε₀ is the absolute permittivity.
substituting, we get
It is given that the magnitude of the electric field that can exist in the capacitor before air breaks down is, E = 3 × 10⁶ N/C.
radius of the plates of the capacitor, r = 69 cm = 0.69 m
Area of the plates, A = πr² = 1.5 m²
Thus, the maximum charge that can be placed on disks without a spark is:
Q = E×ε₀×A
⇒ Q = 3 × 10⁶ N/C × 8.85 × 10⁻¹² F/m × 1.5 m² = 39.8 × 10⁻⁶ C = 39.8 μC.
