If the acceleration is constant (negative or positive) the instantaneous acceleration cannot be
Average acceleration: [final velocity - initial velocity ] /Δ time
Instantaneous acceleration = d V / dt =slope of the velocity vs t graph
If acceleration is increasing, the slope of the curve at one moment will be higher than the average acceleration.
If acceleration is decreasing, the slope of the curve at one moment will be lower than the average acceleration.
If acceleration is constant, the acceleration at any moment is the same, then only at constant accelerations, the instantaneuos acceleration is the same than the average acceleration.
Constant zero acceleration is a particular case of constant acceleration, so at constant zero acceleration the instantaneous accelerations is the same than the average acceleration: zero. But, it is not true that only at zero acceleration the instantaneous acceleration is equal than the average acceleration.
That is why the only true option and the answer is the option D. only at constant accelerations.
Answer:
is time required to heat to boiling point form initial temperature.
Explanation:
Given:
initial temperature of water, 
time taken to vapourize half a liter of water, 
desity of water, 
So, the givne mass of water, 
enthalpy of vaporization of water, 
specific heat of water, 
Amount of heat required to raise the temperature of given water mass to 100°C:
Now the amount of heat required to vaporize 0.5 kg of water:
where:
mass of water vaporized due to boiling
Now the power rating of the boiler:
Now the time required to heat to boiling point form initial temperature:
The molarity of 10% CaCl2 is 0.9%
concentration of the given salt CaCl₂ = 10%
Density of a solution = 1.0835 g/cm³
Volume = m / d
= 100 / 1.0835
= 92.29 litres
Density = mass / volume
1.0835 × 92.29 = mass
mass = 99.99 gram
Thus the molarity can be calculated by = moles of solute / volume of solution multiplied by 100
= 0.9008/ 92.29 X 100 %
= 0.009 X 100 %
= 0.9 %
The molarity of 10% CaCl2 is 0.9%
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brainly.com/question/10710093
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Answer:
Explanation:
Density = Mass / Volume = 850 / 40*10*5 = 0.425 g /cm^3
The source of information was biased. It was like walking along a river bank in the country and asking everybody you meet whether they like fishing. Or asking 500 people sitting in the bleachers whether they like baseball.
I'm sure the scientist would have gotten different data if she interviewed 500 teenagers at neighborhood basketball courts, or 500 teenagers at a rock concert.
