The correct options are:
1 How tall are you?
2How far is it from your house to your school?
3How wide is your refrigerator?
All these measurements involve to measure a length. Instead, the other two options involve to measure different physical quantities; for instance, the question
4 How much does your sister weigh?
Involve to measure a weight (and so, a mass), while the question
5 How warm is it in San Diego?
requires to measure a temperature.
Answer:
the current is 15.68 × 
A
Explanation:
mass = 1000 kg
magnetic fied = 2T
rail separation = 2m
escape velocity is 11.2km/s = 11.2 × 
m/s
distance = 10 km = 
m
to find out
determine the current
solution
we know force F = I×L×B
here I is current and L is rail separation and B is magnetic field
so F = I ×2×2 = 4 I
so
acceleration is a = 
a = 
m/s²
so equation of motion
v²-u² = 2 a S
here u is initial velocity and S is distance and a is acceleration and v is final velocity
11.2 × - 0 = 2× ×
solve we get I
I = 15.68 × A
so the current is 15.68 × A
Answer:
The distance d from the car at which the sound from the stereo can still be discerned = 97720.5 m
Explanation:
Sound intensity heard at distance is related to the distance with the relation = (power of sound at the source)/(surface area of the wall of an imaginary sphere at the distance in question)
I = P/4πd²
Assuming the car has 2 speakers,
P = 0.06 W × 2 = 0.12 W
d = ?
For the intensity of the least discernible sound,
I = 10⁻¹² W/m²
10⁻¹² = 0.12/4πd²
d = 97720.5 m
The frequency of any wave is (speed) / (wavelength).
Frequency = (330 m/s) / (2m) = 165 per second = <em>165 Hz</em>.
Period = 1 / frequency = 1 / (165 per second) = <em>0.0061 second </em>
B, good luck, hope this helps :)
