The ball has an initial speed of 10m/s. This is because it is moving with the balloon. Now the balloonist throws the ball 4m/s with respect to himself, so it means that he gives the ball a extra push of 4m/s, so the total speed is 14m/s. Since it takes 30 seconds to reach the ground, the distance travelled is 14*30=420m.
Answer:
D. 214 kPa
Explanation:
The absolute pressure is given by:
where
p is the absolute pressure
is the atmospheric pressure
is the gauge pressure
In this problem, we have
So, the atmospheric pressure is
The box is at equilibrium, so the net force on the box is zero (the force of gravity on the box is equal to the force exerted up on the box by the surface on which it rests.)
To pick up the box, our upward force must be greater than the force of gravity on the box (the weight). So, we must lift up the box with a force greater than 98 newtons. :)
Answer:
90.9 seconds
Explanation:
m = Mass of liquid = Volume×Density
c = Specific heat
= Change in temperature
t = Time taken
Room temperature = 75 °F
Converting to Celsius
Heat required to raise the temperature of water
Power
Efficiency of the plate
Heat required to raise the temperature of water
Time taken to heat the aceton is 90.9 seconds
Answer:
0.83 ω
Explanation:
mass of flywheel, m = M
initial angular velocity of the flywheel, ω = ωo
mass of another flywheel, m' = M/5
radius of both the flywheels = R
let the final angular velocity of the system is ω'
Moment of inertia of the first flywheel , I = 0.5 MR²
Moment of inertia of the second flywheel, I' = 0.5 x M/5 x R² = 0.1 MR²
use the conservation of angular momentum as no external torque is applied on the system.
I x ω = ( I + I') x ω'
0.5 x MR² x ωo = (0.5 MR² + 0.1 MR²) x ω'
0.5 x MR² x ωo = 0.6 MR² x ω'
ω' = 0.83 ω
Thus, the final angular velocity of the system of flywheels is 0.83 ω.
