Answer:
Explanation:
We shall apply law of conservation of momentum .
m₁ v₁ = m₂ v₂
m₁ = 80 kg
v₁ = ?
m₂ = .43 kg
v₂ = 15 m /s
80 v₁ = .43 x 15
v₁ = .43 x 15 / 80
= .08 m /s
8 cm /s
option A is correct.
Law of conservation of momentum is applied only where no external force acts . Here during the period when ball was thrown , apart from internal force , external force like gravitational force was also acting but we still applied this law because the time duration of action of throw was very small
so we neglected the effect of external force . So it was just an approximation.
23.5 DEGREES is the answer.
Answer: most important, powerful, or influential.
Explanation:
Answer:
B train!
Explanation:
A train travelled at 40 km/hr. (120/3)
B train traveled at 45 km/hr (180/4)
Answer:
3.085 [m].
Explanation:
1) The rule:
m₁*g*l₁=m₂*g*l₂, where m₁ and l₁ - the mass and distance for the small child, m₂ and l₂ - for the big child;
2) according to the condigion l₁+l₂=5, then
3) it is possible to make up the system:
4) finally, l₁=145/47≈3.085 [m].
