" 50 W " means " 50 Watts " or " 50 Joules per second ".
(500,002 J) / (50 J/sec) = <em>10,000.04 seconds</em>
(That's 2 hours 46 minutes 40.04 seconds.)
Answer:
Explanation:
Let equal mass of Ne and Kr be m gm
no of moles of Ne and Kr will be m / 20 and m / 84 ( atomic weight of Ne and Kr is 20 and 84 )
Let the pressure and volume of both the gases be P and V respectively .
The temperature of Ne be T₁ and temperature of Kr be T₂.
For Ne
PV = (m / 20) x R T₁
For Kr
PV = (m / 84) x R T₂
T₁ / T₂ = 84 / 20
We know that
average KE of an atom of mono atomic gas = 3 / 2 x k T
k is boltzmann constant and T is temperature .
KEKr/KENe = T₂ / T₁
= 20 / 84
If the 30 N on the rope were pulled straight up, it would offset the force of gravity ( m g = 10 kg * 9.8 N/kg = 98 N) , leaving a net force up from the ground on the sled of 98-30 = 68 N. Since the rope is pulled at the angle of 25o, only part of the force is in the upward direction, (30N)(sin(25) = (30)(.423) = 12.7. So the net force becomes 98 N down offset by 12.7 up or 98-12.7 = 85.3 N. Ah, there it is: C.
