Answer:
Wnet, in, = 133.33J
Explanation:
Provided that
Pump heat QH = 1000J
Hot temperature TH= 300K
Cold temperature TL= 260K
Given the heat pump is entirely reversible, the performance coefficient expression is formulated as follows:
According to the first law of thermodynamics,
COP(HP, rev) = 1/(1-TL/TH)
COP(HP, rev) = 1/(1-260/300)
COP(HP, rev) = 1/(1-0.867)
COP(HP, rev) = 1/0.133
COP(HP, rev) = 7.5
The power necessary to operate the heat pump is given by
Wnet, in = QH/COP(HP, rev)
Wnet, in = 1000/7.5
Wnet, in = 133.333J. QED
Thus, the 133.33J represents the initial work input during the heat transfer process.
<padditionally...><pbased on="" the="" first="" law="" rate="" at="" which="" heat="" is="" extracted="" from="" lower="" temperature="" reservoir="" calculated="" as="">
QL=QH-Wnet, in
QL=1000-133.333
QL=866.67J
</pbased></padditionally...>
Answer: a) t = 1.8 x 10^2 seconds; b) t = 54 seconds; c) t = 49 seconds. Explanation: a) To determine the time of a stationary passenger on the sidewalk, we use the position formula. Given the constant speed of the walkway, we can calculate the time taken for set distances accordingly. This calculation extends into cases where combined velocities for walking are involved in subsequent queries.
This is somewhat misleading, and I encountered the same question in my homework. An electric field strength of 1*10^5 N/C is provided, along with a drag force of 7.25*10^-11 N, and the critical detail is that it maintains a constant velocity, indicating that the particle is in equilibrium and not accelerating.
<span>To solve, utilize F=(K*Q1*Q2)/r^2 </span>
<span>You'll want to equate F with the drag force, where the electric field strength translates to (K*Q2)/r^2; substituting the values results in </span>
<span>(7.25*10^-11 N) = (1*10^5 N/C)*Q1 ---> Q1 = 7.25*10^-16 C </span>
Answer:
Explanation:
Density is defined as d=m/v.
To find mass, the formula transforms into:
m=d*v
m=2700*54.3
m=146610
m=14.6*10^4