The average speed of the car for the entire trip can be calculate by using:
where S is the total distance covered by the car, and t is the total time taken.
The total distance travelled by the car is:
while the total time taken is:
so, the average speed of the car is:
so, the correct answer is (3) 85 km/h.
Answer:
power emitted is 1.75 W
Explanation:
given data
length l = 5 cm = 5 × m
diameter d = 0.074 cm = 74 × m
total filament emissivity = 0.300
temperature = 3068 K
to find out
power emitted
solution
we find first area that is π×d×L
area = π×d×L
area = π×74 ××5 ×
area = 1162.3892 × m²
so here power emitted is express as
power emitted = E × σ × area × (temperature)^4
put here all value
power emitted = 0.300× 5.67 × 1162.3892 × × (3068)^4
power emitted = 1.75 W