Answer:
the mass of the truck is 2 kg.
Explanation:
Given;
mass of the car, m₁ = 3 kg
initial velocity of the car, u₁ = 40 m/s
initial velocity of the truck, u₂ = 60 m/s
let the mass of the truck = m₂
Apply the principle of conservation of linear momemtum;
m₁u₁ = m₂u₂
m₂ = (m₁u₁) / u₂
m₂ = (3 x 40) / (60)
m₂ = 2 kg
Therefore, the mass of the truck is 2 kg.
Some guidance notes which may help.To calculate the current flow, Ohm's law can be used. This can be written as current=voltage/resistance, or I=V/R. V is 1.5V.R for the copper wire quoted would be calculated as R = resistivity x length/cross sectional area. The area would be calculated from the formula area = pi x diameter squared/4So, R=resistivity x length divided by (pi x diameter squared/4)Until is the resistivity of copper is known, that's about as far as can be gone.Any further questions, please ask.
Answer:
alcohol thermometers are used rather than Mercury thermometers in very cold regions because alcohol has a lower freezing point than Mercury.
Explanation: