Answer:
d. All of these
Explanation:
work is said to be done when a force is applied to an object through a certain distance. the SI unit of workdone is joules or newton per meter
mathematically
workdone = force x distance.
from the answers, work is being done because there is force applied in a certain distance.
- from wagon is used to carry vegetables from a garden.
- pulley is used to get water from a well.
- hammer is used to remove a nail from a wall.
Answer:
3.24×10⁸ J, or 324 MJ
Explanation:
"kWh" is a kilowatt-hour. It's the energy used by 1 kilowatt of power after one hour.
A kilowatt is a kilojoule per second.
90 kWh
= 90 kW × 1 hr
= 90 kJ/s × 1 hr
= 90 kJ/s × 3600 s
= 324,000 kJ
= 324,000,000 J
The energy is 3.24×10⁸ J, or 324 megajoules.
Answer:
The answer is B.
Explanation:
If 212 degrees Fahrenheit is 100 degrees Celsius, then 32 degrees Fahrenheit is 0 degrees Celsius.
were solving for v velocity of the ball after it has hit the bottle. a. momentum ->p=mv->ball + bottle momentum during hit = ball + bottle momentum after hit-> ball (.5*21)+ bottle (.2*0) (it's 0 because the the bottle is standing still) = ball after hit (.5*v)+bottle after hit (.2*30) -> 10.5+0=.5v+6 ->4.5=.5v->v=9m/s
b. if bottle was heavier the ball would be slower so final velocity would decrease
