Answer:
g= 9.81m/s..................
Answer:
-2 m/s
Explanation:
The computation of the acceleration of the block is as follows:
The volume of the block is
V = 1kg ÷ 1,000 kg/m^3 = 1 ÷ 1,000 m^3
Now at the time of submerging in the oil
Net force is

= -2 m/s
If 56.5kJ are needed to raise the temp by 90°C and if the heater is 60% efficient that means that:
60% X y = 56.5kJ
where y is the electrical energy in kJ that the heater will use.
y = 94.2kJ
Answer:
1.04%
Explanation:
Given that,
The power of drill = 3.5 kW = 3500 W
Transferred kinetic energy = 5000 kJ during 15 seconds of use.
We need to find the percentage efficiency of the drill. It can be given by :

Where
Po and Pi are output and input powers.

So,

So, the percentage efficiency of the drill is 1.04%.
Answer:
true
Explanation:
Area = πr²
Differentiating in respect to r
we get,
dA/dr = 2πr
using chain rule,

since r = 4feet
so ,
2π(4) = 8π