F=ma=m(change in velocity/change in time)
Number 1
F=ma
F=55kg(1.1ms^-1/1.6s)=37.8N
Number 2
F=ma
F=0.440kg(10ms^-1/0.02s)=220N
Number 3
F=ma
F=1400kg(15ms^-1/0.73s)=2.88*10^3N or 28,767N
Any questions please feel free to ask.
Answer/solution:
Given :
Mass =5kg
T 1 =20 C,T 2 =100 ∘C
ΔT=100−20=80 ∘C
Q=m×C×ΔT
where C= specific heat capacity of water
=4200J/(kgK)
Q=5×4200×80
=1680000 Joule.
=1680KJ
Answer:
B. The buoyant force on the copper block is greater than the buoyant force on the lead block.
Explanation:
Given;
mass of lead block, m₁ = 200 g = 0.2 kg
mass of copper block, m₂ = 200 g = 0.2 kg
density of water, ρ = 1 g/cm³
density of lead block, ρ₁ = 11.34 g/cm³
density of copper block, ρ₂ = 8.96 g/cm³
The buoyant force on each block is calculated as;

The buoyant force of lead block;

The buoyant force of copper block

Therefore, the buoyant force on the copper block is greater than the buoyant force on the lead block