Answer:
1185 N
Explanation:
From Newton’s second law of motion,
F=ma where m= mass of motorcycle, a is acceleration of the motorcycle and F=Force
Net force acting on motorcycle is given by
Where F is force acting on motorcycle and f is frictional force
Substituting F-f for
hence ma= F- f Substituting a with 3, m with 245Kg and f with 450N as provided
245*3= F- 450
F=245*3 +450= 1185 N
Answer:
a) m = 69.0 kg
b) release some gas in the opposite direction to the astronaut's movement
Explanation:
a) Let's use Newton's second law
F = m a
m = F / a
m = 60.0 / 0.870
m = 69.0 kg
b) when we exert a force on the astronaut it acquires a momentum po, as the astronaut system plus spacecraft is isolated, the momentum is conserved
p₀ = p_f
m v = M v '
v ’=
so we see that the ship is moving backwards, but since the mass of the ship is much greater than the mass of the astronaut, the speed of the ship is very small.
One method to avoid this effect is to release some gas in the opposite direction to the astronaut's movement so that the initial momentum of the astronaut plus the gas is zero and therefore no movement is created in the spacecraft.