The answer to your question will be C. because they are very inexpensive and are readily available but they will eventually deplete because we use them faster than they can be produced we use what has been building up.
Charge = Current/time
Q = It
t = Q/I = 15/20 = 0.75 s
Answer:
force is a derived quantity
work is a fundamental quantity
2.Force is measured in Newton why work is measured in Newton per seconds (N/s)
Explanation:
no
Answer:
It is unsafe
Explanation:
v = Velocity of car = 34 m/s
r = Radius of turn = 190 m
= Coefficient of static friction = 0.5
m = Mass of car = 1600 kg
g = Acceleration due to gravity = 9.81 m/s²
The centripetal force is given by

The frictional force is given by

If the centripetal force is greater than the frictional force then the car will slip which makes it unsafe.
Here, the centripetal force is greater than the frictional force which makes it unsafe to drive it at that speed.
Answer:
Explanation:
power of a heating element = V² / R where V is voltage and R is resistance
putting in the values
5200 = 75² / R
R = 1.082 ohm
Formula for resistance
R = ρ L / S , ρ is resistivity , L is length and S is cross sectional area
1.082 = 5 x 10⁻⁷ x L / (3.83 x 10⁻⁶)
L = 8.29 m
b )
power of a heating element = V² / R , R is new resistance
5200 = 120² / R
R = 2.77 ohm
R = ρ L / S , ρ is resistivity , L is length and S is cross sectional area
2.77 = 5 x 10⁻⁷ x L / (3.83 x 10⁻⁶)
L = 21.22 m