The correct answer to this question would be trees.
Answer:
The change in kinetic energy is 4.3875 kJ
The amount of energy transferred by heat for the process is -66.98 kJ
Explanation:
Given;
mass of the system, m = 13 kg
change in height, Δh = -50 m
initial velocity, u = 15 m/s
final velocity, v = 30 m/s
change in internal energy per mass, ΔU = -5 kJ/kg
The change in kinetic energy is given by;
ΔK.E = K.E₂ - K.E₁
ΔK.E = ¹/₂mv² - ¹/₂mu²
ΔK.E = ¹/₂m(v² - u²)
ΔK.E = ¹/₂ ₓ 13 (30² - 15²)
ΔK.E = 4387.5 J
ΔK.E = 4.3875 kJ
The amount of energy transferred by heat for the process;
Q = W + ΔP.E + ΔK.E + ΔU
Where;
ΔP.E = mgΔh
ΔP.E = 13 x 9.8 x (-50)
ΔP.E = -6370 J = -6.37 kJ
W = 0
ΔU = -5kJ/kg x 13kg
ΔU = -65 kJ
Q = W + ΔP.E + ΔK.E + ΔU
Q = 0 + (-6.37) + (4.3875) + (-65)
Q = -66.98 kJ
120 km/h = 33.33 m/s 10.8 km/h/s = 3 m/s/s the motorist will cover a distance of 33.33 m x T(seconds) the police officer will cover a distance of 1/2 (3) T^2 they will be at the same point when 33.33T = 1.5 T^2 33.33 = 1.5 T 3T = 66.66 T = 22.22 seconds it will take the officer 22.22 seconds to catch the motorist. the officer will be moving V=AT = 3m/s x 22.22 seconds = 66.66 m/s almost 240 km/h (239.976 km/h)
111.0 because 111.009 rounds off to 111.01, thus rounding again off to 111.0
Power is the rate at which work is done (2nd option)
