Internal energy of the system changes by ΔE = 178 J.
Heat given to the system = Q = +658 J.
According to the first law of thermodynamics,
ΔE = Q + W
178 = 658 + W
∴ W = 178-658 = -480 J
Minus sign indicates that work is done by the system.
Answer:
f=-1380N
Explanation:
A karate master wants to break a board by hitting the board swiftly with his hand. The master's hand has a mass of 0.30 kg, and as it strikes the board, his hand has a velocity of 23.3 m/s. The master contacts the board for 0.0050 seconds
.the concluding part to the question should be
What is the impact force (impulse) on the board?
solution
from the Newton's second law of motion which states that
the rate of change in momentum is directly proportional to the force applied
f=m(v-u)/t
f=0.3(0-23.3)/0.005
f=-1380N
f=force impact
m=mass of the karates master's hand
t=time for the impact
v=0m/s final velocity
u=initial velocity
Answer:
The correct answer is - option A. The mashed potatoes will transfer heat into the gravy.
Explanation:
In this case, where Yamel heats the mashed potatoes but forgets to heat the gravy and put the cold gravy on the hot mashed potatoes. Heat always transfers from the high-temperature object to the low-temperature object. So the hot mashed potatoes will transfer the heat to the gravy according to option A. Cold is not a form of heat but the condition of absence of heat or very low temperature.
Thus, the correct answer is - option A. The mashed potatoes will transfer heat into the gravy.
Answer:
A. 24 m, 14 m/s
B. 8.0 m
Explanation:
Given:
x₀ = 6.0 m
v₀ = 4.0 m/s
a = 5.0 m/s²
t = 2.0 s
A. Find: x and v
x = x₀ + v₀ t + ½ at²
x = (6.0 m) + (4.0 m/s) (2.0 s) + ½ (5.0 m/s²) (2.0 m/s)²
x = 24 m
v = at + v₀
v = (5.0 m/s²) (2.0 s) + (4.0 m/s)
v = 14 m/s
B. Find x when v = 6.0 m/s.
v² = v₀² + 2a (x − x₀)
(6.0 m/s)² = (4.0 m/s)² + 2 (5.0 m/s²) (x − 6.0 m)
x = 8.0 m
