Answer:
a) their potential energy increases.
Explanation:
Ohm's Law is
R= V/I
Where R= Resistance
V= potential difference or potential energy
I= current or conduction electron flow rate
Clearly R and V are directly proportional i-e Potential energy increases with resistance.
You haven't said what 'high' resistance or 'low' current means, so there's way not enough info to nail the statement as true or false. The most precise answer is "certainly could be but not necessarily". Anyway, the current in the circuit depends on BOTH the resistance AND the voltage. So without knowing the voltage too, you can't say anything about the current.
Answer:
1) f= 8.6 GHz
2) t= 0.2 ms
Explanation:
1)
- Since microwaves are electromagnetic waves, they move at the same speed as the light in vacuum, i.e. 3*10⁸ m/s.
- There exists a fixed relationship between the frequency (f) , the wavelength (λ) and the propagation speed in any wave, as follows:
- Replacing by the givens, and solving for f, we get:
⇒ f = 8.6 Ghz (with two significative figures)
2)
- Assuming that the microwaves travel at a constant speed in a straight line (behaving like rays) , we can apply the definition of average velocity, as follows:
where v= c= speed of light in vacuum = 3*10⁸ m/s
d= distance between mountaintops = 52 km = 52*10³ m
⇒ t = 0.2 ms (with two significative figures)
The angular acceleration of a rotating object is given by
where
is the final angular speed of the object
is its initial angular speed
is the time taken to accelerate
For the wheel in our problem,
,
and
, so its angular acceleration is
1st Law: Objects that are in motion tend to stay in motion. This motion can change with external forces.
<span>If you were to stop pedaling on bike while in motion, you will notice that you will keep moving. This is because a moving body (you) has inertia. If there wasn't any friction between the tires and the ground, between the axles and wheel, any air resistance, or any other force that acts against you, then you could be coasting indefinitely! </span>
<span>2nd Law: Force is equal to the mass times acceleration. </span>
<span>When you pedal, you are applying a force onto the pedal. This force is then translated through tension to apply torque onto the wheel. Turning the wheel will make you accelerate in the lateral direction. </span>
<span>3rd Law: For every action, there is an equal and opposite reaction. </span>
<span>Without this, you could pedal and pedal, but you will be not go anywhere! It is essentially the friction between the tires and the ground that propels you forward. If the ground did not apply to the tire the same amount of force that the tire was applying to the ground, the tire would not "catch" and no friction would be applied. And if there was no third law, the weight of you and your bike would "sink" into the ground because the ground would not be applying a normal force back onto you.
hope this helps and if you have any questions just hmu and ask :)</span>
