The answer for the online test is going to be the last one, D
All of the above hope this could
Help!
Answer: The answer will be A
Explanation:
There is acceleration in all cases velocity changes. In options b and c the speed is constant, then there is no acceleration. In option a, the car was moving and then stop, therefore, its speed decrease to zero, and that represent an acceleration.
Answer:U(x) = 30x^2 +6x^3
V^2=8.28m/s
Explanation:The law of conservation of energy is given by K1+U1= K2+U2 ...eq 1
Kinetic energy K.E= 1/2 mv^2
Restoring force function F(x)= -60x - 18x^2
But F(x)= -dU/dx
dU(x)=-F(x)dx
Integrating U(x)= -integral F(x)dx + U(0)
Substituting, we get
U(x) = - integral(-60x-18x^2)dx+U(0)
U(x)= 30x^2+6x^3+U(0)
U=0 at x=0
Therefore U(x)= 30x^2+6x^3
b) Given : x1=1.00m,x2= 0.50m ,V1=0, V2=?
Substituting into eq (a)
U1= 30(1.00)^2+6(1.00)^3=36J
Using x2=0.5 into eq(a)
U2=30(0.50)^2+6(0.50)^3=8.25J
Object at rest K1=0
0+36=K2+8.25
K2=27.75J
Given; m =0.900kg, V2=?
27.75=1/2×0.900×V2^2
V2= SQRT(2×27.75)/0.81
V2= 8.28m/s
