<h3><u>Answer;</u></h3>
<em>Work = 125 joules </em>
<h3><u>Explanation and solution</u>;</h3>
- Work is the product of force and the distance covered. Therefore, Work = force × distance.
- Work is measured in joules.
- Work is also a change in energy, such that work is done when energy changes, so when kinetic energy, or potential energy changes the there is work being done.
Thus; kinetic energy = work done
Kinetic energy = 1/2mv²
= 1/2 × 10× 5²
= 5 × 25
= 125 joules
Hence, work done is 125 joules.
Q: The small piston of a hydraulic lift has a cross-sectional of 3.00 cm2 and its large piston has a cross-sectional area of 200 cm2. What downward force of magnitude must be applied to the small piston for the lift to raise a load whose weight is Fg = 15.0 kN?
Answer:
225 N
Explanation:
From Pascal's principle,
F/A = f/a ...................... Equation 1
Where F = Force exerted on the larger piston, f = force applied to the smaller piston, A = cross sectional area of the larger piston, a = cross sectional area of the smaller piston.
Making f the subject of the equation,
f = F(a)/A ..................... Equation 2
Given: F = 15.0 kN = 15000 N, A = 200 cm², a = 3.00 cm².
Substituting into equation 2
f = 15000(3/200)
f = 225 N.
Hence the downward force that must be applied to small piston = 225 N
Answer:
$ 18.75
Explanation:
given,
capacity of the Dave’s car = 12 gallons
Assuming that the tank is 3/8 full before
Cost of gas per gallon = $2.50 per gallon of gas
Volume Dave have to fill
=
=
of full tank
=
volume Dave have to fill = 7.5 gallons
total money Dave spent
= 7.5 gallons x $2.50
= $ 18.75
Dave have to spend $ 18.75 to fill tank to it capacity.
The ball has an initial speed of 10m/s. This is because it is moving with the balloon. Now the balloonist throws the ball 4m/s with respect to himself, so it means that he gives the ball a extra push of 4m/s, so the total speed is 14m/s. Since it takes 30 seconds to reach the ground, the distance travelled is 14*30=420m.
Magnet moving left to right
