Answer:
300000 J / 400 J/s = 750 s = 12.5 minutes
Explanation:
Answer:
180 W
Explanation:
The work done by the man against gravity is equal to its gain in gravitational potential energy:
where
(mg) = 720 N is the weight of the man
is the change in height
Substituting,
The power he must deliver is given by
where
W = 3600 J
t = 20 s is the time taken
Substituting,
To find out scientific notation, you want to make sure that number is less than 10. So do 5.000000, you don't rally need the zeros but I just want to make my point. So use 10^x meaning ten the whatever power adds zeros like 5.000000x10^6 meaning it is increasing it by six zeros moving it out of the decimals and letting become 5,000,000.
Answer: 0.790 g/cm3
Explanation:
The density of acetone is 790 Kg/m3.
To convert from Kg to g we multiply by 1000 (1 Kg = 1000 g)
To convert from m3 to cm3 we multiply by 10∧6
So, The density of acetone in (g/cm3) = (790 x 1000) / (10∧6) = 0.79 g/cm3
Answer:
Explanation:
Given
Each student exert a force of 
Let mass of car be m
there are 18 students who lifts the car
Total force by 18 students 
therefore weight of car 
mass of car 
(b)
