Answer:
B. 81
Explanation:
When you multiply two numbers, round the answer to the least number of significant figures available. 67.6 has three significant figures, and 1.2 has two significant figures. So we round to two significant figures.
Answer:
given,
mass of copper = 100 g
latent heat of liquid (He) = 2700 J/l
a) change in energy
Q = m Cp (T₂ - T₁)
Q = 0.1 × 376.812 × (300 - 4)
Q = 11153.63 J
He required
Q = m L
11153.63 = m × 2700
m = 4.13 kg
b) Q = m Cp (T₂ - T₁)
Q = 0.1 × 376.812 × (78 - 4)
Q = 2788.41 J
He required
Q = m L
2788.41 = m × 2700
m = 1.033 kg
c) Q = m Cp (T₂ - T₁)
Q = 0.1 × 376.812 × (20 - 4)
Q = 602.90 J
He required
Q = m L
602.9 = m × 2700
m =0.23 kg
Explanation:
rent me for brainliest pls
What about cod my guy which one are we talking ?
Given that,
Mass of object, m = 55 kg
Mechanical energy of the object, M = 4306 J
Potential energy, P = 2940 J
We know that the mechanical energy is the sum of kinetic and potential energy such that,
Mechanical energy = kinetic energy + potential energy
Kinetic energy is given by :
v is velocity of object
So, the velocity of object is 7.04 m/s.
