Explanation:
Using kinematics,
t = 4s
u = 0m/s
a = 9.8m/s^2
Therefore v = u + at = 0 + (4)(9.8) = 39.2m/s.
Answer:
- Here we use the conservation of momentum theorem.
- m stands for mass, and v stands for velocity. The numbers refer to the respective objects.
- m1v1 + m2v2 = m1vf1 + m2vf2
- Since the equation is perfectly inelastic, the final velocity of both masses is the same. Let’s account for this in our formula.
- m1v1 + m2v2 = vf(m1 + m2)
<u>Let’s substitute in our givens.</u>
(0.002 kg)(700 m/s) + (5 kg)(0 m/s) = vf(0.002 kg + 5 kg)
I assume you are proficient in algebra I, so I will not include the steps to simplify this equation.
Note that I have considered the bullet’s velocity to be in the positive direction,
The answer is vf = 0.280 m/s
A. At the top. At this point, the child is highest, and they are not moving. Their potential energy is much greater.
Answer:
Explanation:
The force of the lake bottom on the boat = force the boat exerts on the bottom
force the boat exerts on the bottom = weight of the boat - buoyant force on the boat
so
The force of the lake bottom on the boat = weight of the boat - buoyant force on the boat
So
The force of the lake bottom on the boat will be less than its weight .
Answer:
a)η = 0.088
b) η = 0.5
Explanation:
a) The attached figure shows the P-V diagram for the process described in the exercise. According to that figure, the work during process 1-2 is equal to:
W(1-2) = -n*R*T1*ln(vi/vf) = -n*R*T1*ln(V/(V/2)) = -n*R*T1*ln(2)
the work during process 2-3 is equal to:
W(2-3) = nR*(T2-T1)
The work done during the 3-1 process equals zero, because the volume is constant. The specific heat for the molar specific heat equals:
cp = 7*R/2, where R is gas constant.
Qin = n*cp*(T2-T1) = 7*n*R/2*(T2-T1)
the efficiency of the cycle is equal to:
η = (W(1-2) + W(2,3))/Qin = (-n*R*T1*ln2 + n*R*(T2-T1))/(7*n*R/2*(T2-T1) = (2/7)*(1-(ln2/((T2/T1)-1)))
if we write the expression between volume and temperature, we have:
T2/T1 = v1/v2
T2/T1 = v/(v/2))
T2/T1 = 2
η = (2/7)*(1-(ln2/(2-1))) = 0.088
b)
The equation for efficiency of Carnot will be equal to:
η = 1-(T1/T2) = 1 - (1/2) = 0.5