Answer:
B: leaving metal outside in the rain until rust forms an it's surface
Those two units can be compared to a 'mile per hour' and a 'mile per hour - hour'.
One is a rate. The other is a quantity, after maintaining a rate for some time.
-- 'Joule' is a unit of energy. It's the amount of work (energy) you do
when you push with a force of 1 newton though a distance of 1 meter.
Lifting 10 pound of beans 3 feet off the floor takes about 40.7 joules of energy.
-- 'Watt' is a <u><em>rate</em></u> of using energy . . . 1 joule per second.
If you lift 10 pounds 3 feet off the floor in 1 second, your <em>power</em> is 40.7 watts.
-- 'Watt-second' is the amount of energy used in one second,
at the rate of 1 joule per second . . . 1 joule.
-- 'Watt-hour' is the amount of energy used in one hour,
at the rate of 1 joule per second . . . 3,600 joules.
-- 'Kilowatt' is a bigger <em>rate</em> of using energy . . . 1,000 joules per second.
-- 'Kilowatt - second' is the amount of energy used in one second,
at the rate of 1,000 joules per second . . . 1,000 joules .
-- 'Kilowatt - hour' is the amount of energy used in one hour,
at the rate of 1,000 joules per second . . . 3,600,000 joules .
Depending on where you live, 3,600,000 joules of energy bought
from the electric company costs something between 5¢ and 25¢.
v = initial velocity of launch of the stone = 12 m/s
θ = angle of the velocity from the horizontal = 30
Consider the motion of the stone along the vertical direction taking upward direction as positive and down direction as negative.
v₀ = initial velocity along vertical direction = v Sinθ = 12 Sin30 = 6 m/s
a = acceleration of the stone = - 9.8 m/s²
t = time of travel = 4.8 s
Y = vertical displacement of stone = vertical height of the cliff = ?
using the kinematics equation
Y = v₀ t + (0.5) a t²
inserting the values
Y = 6 (4.8) + (0.5) (- 9.8) (4.8)²
Y = - 84.1 m
hence the height of the cliff comes out to be 84.1 m
Answer:
his speeds while going to city is 10 mph and while his round trip the speed will be 9 mph
Explanation:
Let say the speed of the bicycle while he moves towards the city is "v"
now the speed of the round trip must be smaller by 1 mph
so its speed for round trip will be
now we know that total time of the motion is 19 hr
so we will have
so we will have
by solving above equation we have
so his speeds while going to city is 10 mph and while his round trip the speed will be 9 mph
Answer:
2Ω
Explanation:
If a 18Ω resistance is cut into three equal parts each of the resistance will be 18Ω/3 = 6Ω
Equivalent ratio in parallel is expressed as:
1/R = 1/6 + 1/6 + 1/6
1/R = 3/6
Cross multiply
3R = 6
R = 6/3
R = 2Ω
Hence the required equivalent resistance is 2Ω
