Scalar quantity are physical quantities that have just magnitude, not direction.
- It is always positive.
- Examples: Speed, distance
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:
Assuming there are 28 days in each month,
750W = 0.75kW
Cost of electric bill = 0.75 × 8 × 28 × $0.23
= $38.64
Step 1 : Get your supply list together
Step 2 : Pick what model you want to do
Step 3 : Ask for a partner
Step 4 : Complete the model and take your time.
Step 5 : Read the directions carefully
