Answer:
The force of friction that acts on him is

Explanation:
The firefighter with an acceleration of 3m/s^2 take the gravity acceleration as 10m/s^2 isn't necessary to know the coefficient of friction just to know the force of friction:




Sole to Fk



At surface,
v = kq/r
And potential energy of an electron is given by,
PE = -ev = -ekq/r
At escape velocity,
PE + KE = 0.
Therefore,
1/2mv^2 - ekq/r =0
1/2mv^2 = ekq/r
v = Sqrt [2ekq/mr], where v = escape velocity, e = 1.6*10^-19 C, k = 8.99*10^9 Nm^2/C^2, m = 9.11*10^-31 kg, r = 1.1*10^-2 m, q = 8*10^-9 C
Substituting;
v = Sqrt [(2*1.6*19^-19*8.99*10^9*8*10^-9)/(9.11*10^-31*1.1*10^-2)] = 47949357.23 m/s ≈ 4.795 *10^7 m/s
Answer:
B. 161.5 J
Explanation:
= Number of moles = 0.37
= Rise in the temperature of the oxygen gas = 15 K
= heat added in order to raise the temperature
= specific heat at constant pressure = 3.5
At constant pressure, heat is given as

Answer:
2.6 m
Explanation:
The work done by the bird is given by

where
F is the force exerted
d is the distance covered
In this problem, we know:
is the work
is the force
Solving the equation for d, we find the distance covered by the bird:
