Answer:
a)
, b)
, c)
.
Explanation:
a) Let assume that car travel on a horizontal surface. The equations of equilibrium of the car are:


After some algebraic handling, the following expression for the propulsion force is constructed:



b) The power require to move the car at a speed of 5 meters per second is:



c) The efficiency of the car is:


Answer:
41.053 A
Explanation:
given,
three phase kVA = 25-kVA
voltage = 440 Volt
current = ?
To determine three phase kVA when volts and amperes are know
three phase kVA = 1.73 x V x I


I = 32.84 A
the maximum overcurrent protection value is equal to
= 125 % of I
= 1.25 x 32.84
= 41.053 A
Answer:
As b ∝ (L/r²) and
the distance of the sun from the earth is 0.00001581 light years
and
the distance of the Sirius from the earth is 8.6 light years
hence,
the Sun appear brighter in the sky
Explanation:
The brightness (b) is directly proportional to the Luminosity of the star (L) and inversely proportional to the square of the distance between the star and the observer (r).
thus, mathematically,
b ∝ (L/r²)
now,
given
L for sirius is 23 times more than the sun i.e 23L
now,
the distance of the sun from the earth is 0.00001581 light years
and
the distance of the Sirius from the earth is 8.6 light years
thus,
using the the relation between conclude that the value of brightness for the Sirius comes very very low as compared to the value for brightness for the Sun.
hence, the sun appears brighter
There all diffrent speeds