Answer:
The number of calories needed is 6c.
Explanation:
The amount of energy needed to raise the temperature of water of mass is
where is the specific heat capacity of water.
Putting in numbers into equation (1), we get:
which is the number of calories needed.
The working equation would be Vf (final velocity) = Vi
(initial velocity) + a (acceleration) t (time). The given data are the initial
velocity (5.0 m/s), acceleration (-2.5 m/s^2, negative since it is said to
decelerate) and the final velocity (0 m/s, since it will put to a stop). The
time would be 2 seconds.
Answer:1.14.102 on the side of 10
Explanation:
Answer:
3) From 37 km/h to 47 km/h
Explanation:
Kinetic Energy: This is the energy posses by a body in motion. The Unit of kinetic energy is joules. And it is expressed mathematically as,
Ek = 1/2mv².................... Equation 1
ΔEk = 1/2m(v₂² - v₁²)...................... Equation 2
Where ΔEk = change in kinetic energy, m = mass of the body, v₁ = initial velocity, v₂ = final velocity of the body.
<em>Note: The mass of the car is constant in both cases.</em>
When the body accelerate from 27 kh/h to 37 km/h
ΔEk₁ = 1/2m(37²-27²)
ΔEk₁ = 1/2m(640)
ΔEk₁ = 320m J.
When The body accelerate from 37 km/h to 47 km/h
ΔEk₂ = 1/2m(37²-47²)
ΔEk₂ = 1/2m(840)
ΔEk₂ = 420m J
From the above,
ΔEk₂ > ΔEk₁.
Hence the correct option is 3) From 37 km/h to 47 km/h
Answer:
C) 58.8 J
Explanation:
Initially, the cart has only potential energy.
PE = mgh
PE = (3.0 kg) (9.8 m/s²) (4.0 m)
PE = 117.6 J
Halfway down the hill, half the potential energy has been converted to kinetic energy.
KE = 117.6 J / 2
KE = 58.8 J