I'll assume you are looking for the mass of the object, since that is the missing piece of the puzzle.
The important equation for heat and energy is
Energy = mass × specific heat × change in temperature
Things we know:
Energy needed is 350 J.
Specific heat = 1.2 J/g°C
Temp. change = (30-20)°
Now we just need to plug those in and rearrange the formula to find the mass!
350 = mass × 1.2 × 10
If you did this then it could lead to cheating or someone else getting hurt.
Explanation:
we use the formula for that 6s duration ....
<h2> S = ut + 1/2 at² </h2><h3>s = displacement </h3><h3>u = initial velocity </h3><h3>a = acceleration </h3><h3>t = time </h3>
so , S = (5 × 6) + (1/2 × 2 × 6 × 6 )
S = 30 + 36
<h3> S = 66m</h3>
and we can use this formula to find the final velocity.......
<h2> V = U + at </h2><h3>V = final velocity </h3><h3>a = acceleration </h3><h3>u = initial velocity </h3><h3>t = time </h3>
so , V = 5 + (2×6)
V = 5 + 12
<h3> V = 17m/s </h3>
Answer:
a) W = 6.75 J and b) v = 3.87 m / s
Explanation:
a) In the problem the force is nonlinear and they ask us for work, so we must use it's definition
W = ∫ F. dx
Bold indicates vectors. In a spring the force is applied in the direction of movement, whereby the scalar product is reduced to the ordinary product
W = ∫ F dx
We replace and integrate
W = ∫ (-60 x - 18 x²) dx
W = -60 x²/2 -18 x³/3
Let's evaluate between the integration limits, lower W = 0 for x = -0.50 m, to the upper limit W = W for x = 0 m
W = -30 [0- (-0.50) 2] -6 [0 - (- 0.50) 3]
W = 7.5 - 0.75
W = 6.75 J
b) Work is equal to the variation of kinetic energy
W = ΔK
W = ΔK = ½ m v² -0
v =√ 2W/m
v = √(2 6.75/ 0.90)
v = 3.87 m / s
