Answer:
Seven
Explanation:
The rules for significant digits are:
- Non-zero digits are always significant.
- Zeros between significant digits are also significant.
- Trailing zeros are significant only after a decimal point.
Here, the 2, 4, 9, and 2 are significant because they are non-zero digits.
The first two 0s are significant because they are between significant digits.
The last 0 is significant because it is a trailing zero after a decimal point.
Therefore, all seven digits are significant.
The correct answer is 19.72 °C. The first step is to determine the amount of heat that was lost per gram (30,000 J) / (390 g) = 76.92 J/g. Then to determine the temperature change, divide 76.92 J/g with the given specific heat of milk (76.92 J/g) / (3.9 J/g°C) = 19.72 °C.
The answer would be option D "a ball sitting on a shelf." Potential energy is the amount of energy a object has while it's at rest.. (or not moving) Kinetic energy is how much energy a object is while it's moving. So in this case it's option D because a ball sitting on a shelf isn't moving therefore it has potential energy. It's not option A because thats a example of kinetic energy since how the roller coaster is moving. It's not option B because it's kinetic energy because the bike is moving. It's also not option C because it's kinetic energy because the bird is moving.
Hope this helps!
Lines of Force around an Electromagnet. ... The magnetic field strength of an electromagnet is therefore determined by the ampere turns of the coil with the more turns of wire in the coil the greater will be the strength of the magnetic field.
