Answer:
Explanation:
Let acceleration of fall be a .
v² = u² + 2as
v = 3.8 m /s
u = 0
s = 3.5 m
3.8² = 0 + 2 x a x 3.5
a = 2.06 m /s²
Since this acceleration is less than g , an upward force is acting on the firefighter in the form of friction . Let this force be F . Let mass of the firefighter be m .
m = 765 / 9.8
= 78.06 kg
mg - F = ma
765 - F = 78.06 x 2.06
765 - F = 160.8
F = 604.2 N .
Answer:
Option C is correct.
The magnitude of the field is reduced to half at twice the distance,
Explanation:
The magnetic field produced in a long, straight conductor carrying a current I at distance r is given by
B = μ₀I/2πr
Where μ₀ is the constant permeability of free space.
If we increase the distance by twice then
B = μ₀I/2π(2r)
B = μ₀I/2πr(2)
B = B/2
Therefore, the magnitude of magnetic field is reduced by B/2 at twice the distance.
The skydiver jumping from a plane high up in the sky would most likely experience various energy transformation. For starters, it would undergo a very large gravitational potential energy because of its much higher elevation. After jumping, this energy would eventually transform to kinetic energy due to the force exerted by the gravity.
The final temperature is 34.91°C
<u>Explanation:</u>
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Initial volume, V1 = 362m³
Final volume, V2 = 632m³
Initial temperature, T1 = 20°C
Final temperature, T2 = ?
We know,
V1/T1 = V2/T2
362/20 = 632/T2
T2 = 34.91°C
Therefore, the final temperature is 34.91°C
