Change in speed = (speed at the end) minus (speed at the beginning)
= (0 - 20 m/s) = -20 m/s
Acceleration = (change in speed) / (time for the change)
= (-20 m/s) / (3.5 sec) = -5.71 m/s²
Notice that this story probably didn't happen on Earth, because
the acceleration due to gravity on Earth is 9.8 m/s².
The light transmitted by a filter is <em>less bright </em>than the light that hits it.
A filter only absorbs/removes part of the light that hits it. That means it removes some energy from the incident light. The remaining light carries less energy, so it must be less bright.
C is the answer Because chemical energy Create heat And thermal power relates to heat energy
Answer: mechanical efficieny.
Efficieny is also expressend as percent. The formula for mechanical efficiency as percent is the ratio work output to wor input times 100.
The ideal mechanical efficiency for a machine would be 1 or 100% which means that all the input work is converted into output work. But this is just an idealization as the friction and other losses of energy make it imposible to reach 100% efficiency in reality, so the mechanical efficiency of real machinces is less than 100% or 1.
Answer:
A) mr = 100 kg
B) Fr = 210N
C) Ft = -199.5N
Explanation:
By conservation of the momentum:
mt*Vo = (mr + mt) * Vf Solving for mr:
mr = mt*Vo / Vf - mt = 100 kg
The average force on the receiver:
mr *(Vf - 0) = Fr * Δt Solving for Fr:
Fr = 210 N
The average force on the tackler:
mt * (Vf - Vo) = Ft * Δt Solving for Ft:
Ft = -199.5 N
