Answer:
<em>P = 2,000 W</em>
Explanation:
<u>Work and Power
</u>
Work is the amount of energy transferred by a force over a distance. It's a scalar quantity, with SI units of joules.
If both the force F and displacement s are parallel, then we can use the equivalent scalar formula:
W=F.s
Power is the amount of energy transferred or converted per unit of time. In the SI, the unit of power is the watt, equal to one joule per second.
The power can be calculated as:
Where W is the work and t is the time.
A box with a weight of 1,000N is lifted by s=20 m by a rope and pulley system. The system exerts a force equal to the weight of the box, thus F=1,000 N. The work done by the system is:
W =1,000 N * 20 m
W = 20,000 J
Now we calculate the power developed by the system in t=10 seconds:
P = 2,000 W
Answer:
Continuous random variable
Explanation:
The distance that baseball travels after being hit is a random variable and it assume any real value defined on the sample space.
The distance is measurable and thus is continuous random variable because continuous variable cannot be counted but could be measured.
This statement is false: More hitting among particles creates more energy which means a higher temperature, which in turn means higher pressure. Thus, this is a false statement.
Hope this helps!
Answer:
64.1°C
Explanation:
mass of automobile, M = 1500 kg
velocity, v = 35 m/s
mass of each brake, m = 8 kg
specific heat of iron, c = 448 J/kg°C
According to the conservation of energy
the kinetic energy of automobile = thermal energy of brakes
0.5 Mv² = 4 x m x c x ΔT
where, ΔT is the rise in temperature of the brake
0.5 x 1500 x 35 x 35 = 4 x 8 x 448 x ΔT
ΔT = 64.1°C
Thus, the change in temperature of each brake is 64.1°C.
W=Fd
W=22,000N*(2,000m)
W=44,000,000J