There are 3 significant figures, if that answers the question.
Answer:

Explanation:
Hello,
In this case, considering that the acceleration is computed as follows:

Whereas the final velocity is 28.82 m/s, the initial one is 0 m/s and the time is 4.2 s. Thus, the acceleration turns out:

Regards.
Answer: F = 33.6 N
Explanation: work = force · distance or W = F·s
Force F = W/s = 504 J/15 m
Heat required to raise the temperature of a given system is

here we know that
m = mass
s = specific heat capacity
= change in temperature
now as we know that
mass of wood = 5 kg
mass of aluminium pan = 2 kg
change in temperature = 45 - 20 = 25 degree C
specific heat capacity of wood = 1700 J/kg C
specific heat capacity of aluminium = 900 J/kg C
now here we will find the total heat to raise the temperature of both




So heat required to raise the temperature of the system is 257500 J
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