Answer
given.
Mass of big fish = 15 Kg
speed of big fish = 1.10 m/s
mass of the small fish = 4.50 Kg
speed of the fish after eating small fish =?
a) using conservation of momentum
m₁v₁ + m₂v₂ = (m₁+m₂) V
15 x 1.10 + 4.50 x 0 = (15 + 4.5)V
16.5 = 19.5 V
V = 0.846 m/s
b) Kinetic energy before collision


KE₁ = 9.075 J
Kinetic energy after collision

KE₂ = 6.98 J
Change in KE = 6.98 - 9.075 = -2.096 J
hence,
mechanical energy was dissipated during this meal = -2.096 J
<span>10 hertz
Hertz is the frequency of oscillation which is the number of oscillations per second. So if something takes 0.10 s per oscillation, divide 1 second by the period to get the frequency. So
1 / 0.10s = 10 1/s = 10 Hertz
Therefore the object is vibrating at 10 hertz.</span>
Answer: 8Ω
Explanation:
Since there are two resistors of 4Ω
connected in series, the total resistance (Rtotal) of the circuit is the sum of each resistance.
i.e Rtotal = R1 + R2
R1 = 4Ω
R2 = 4Ω
Rtotal = ?
Rtotal = 4Ω + 4Ω
Rtotal = 8Ω
Thus, the total resistance of the circuit is 8Ω
Answer: The increase in temperature of the nail after the three blows is 8.0636 Kelvins. The correct option is (d).
Explanation:
Kinetic energy of the hammer ,K.E.=

Half of the kinetic energy of the hammer is transformed into heat in the nail.
Energy transferred to the nail in one blow =

Total energy transferred after 3 blows,Q =
Mass of the nail = 15 g = 0.015 kg
Change in temperature =
Specif heat of the steel = c = 448 J/kg K



The increase in temperature of the nail after the three blows is 8.1 Kelvins.Hence, correct option is (d).