Answer:

Explanation:
As we know that the rate of heat transfer due to temperature difference is given by the formula

here we know that

A = 4 m x 7 m
thickness = 30 cm
temperature difference is given as

now we have


671mi/hr
= 671/60min (calculates miles/min)
= (671/60) ÷ 60seconds (calculates miles/sec)
((671/60) ÷ 60)× 1609m
= 299.899 meters/sec
= 299.90m (round off to 2 decimals )
Answer:
1500 Joules
Explanation:
Work = Force x Distance
When multiplying by 10 you simply shift all the digits to the
left and append a 0 to the end.
so 150 x 10 = 1500 Joules
Answer:
The magnitude of the uniform magnetic field exerting this torque on the loop is 1.67 T
Explanation:
Given;
radius of the wire, r = 0.45 m
current on the loop, I = 2.4 A
angle of inclination, θ = 36⁰
torque on the coil, τ = 1.5 N.m
The torque on the coil is given by;
τ = NIBAsinθ
where;
B is the magnetic field
Area of the loop is given by;
A = πr² = π(0.45)² = 0.636 m
τ = NIBAsinθ
1.5 = (1 x 2.4 x 0.636 x sin36)B
1.5 = 0.8972B
B = 1.5 / 0.8972
B = 1.67 T
Therefore, the magnitude of the uniform magnetic field exerting this torque on the loop is 1.67 T
Answer:
i = 4.9 A
Explanation:
The expression for the magnetic force in a wire carrying a current is
F = i L x B
bold letters indicate vectors.
The direction of the cable is towards the East, the direction of the magnetic field is towards the North, so the vector product is in the vertical direction (z-axis) upwards and the weight of the cable is vertical downwards. Let's apply the equilibrium condition
F - W = 0
i L B = m g
They indicate the linear density of the cable λ = 0.2 kg / m
λ = m / L
m = λ L
we substitute
i B = λ g
i = 
let's calculate
i = 0.2 9.8 / 0.4
i = 4.9 A