Answer:
a. The object will attract the glass rod.
b. The object will repel the glass rod.
Explanation:
a. When you rub a plastic rod with wool, it becomes negatively charged. This is because the wool material loses some of its electrons to the plastic rod. The wool becomes positively charged while the plastic rod becomes negatively charged.
Hence, for an object to repel the negatively charged plastic rod, it must also be negatively charged. This is because objects with like charges repel one another.
On the other hand, when you rub a glass rod with a silk material, it becomes positively charged. This is because the glass rod loses its electrons to the silk material. The silk material then becomes negatively charged, while the glass rod becomes positively charged.
Therefore, the negatively charged object will attract the already positively charged glass rod.
b. For an object to attract a negatively charged plastic rod, then it must be positively charged, since unlike charges attract.
So, a positively charged object will repel the negatively charged glass rod.
Explanation:
- A thermometer does measure the temperature of a body and not the heat. It is known that temperature is a measure of average kinetic energy.
Therefore, the statement a thermometer measures the average kinetic energy of a substance is correct.
- Heat is a form of energy as it can make a colder substance become hot and it moves from one place to another. Thus, the statement heat is a form of energy is correct.
- Also, heat flows from hotter substance to colder substance. Hence, the statement heat flows from a colder substance to a hotter substance is correct.
- Convection is a property of fluids or gases which makes less denser (hot) material to rise and more denser (colder) material to sink.
Therefore, the statement convection occurs only in liquids and gases is correct.
- All substances radiate heat is an incorrect statement. For example, a thermos bottle does not radiate heat.
- Temperature of our body is about 98.4 degree celsius and hence we can conclude that the statement our body temperature is always equal to the temperature around us is incorrect.
Answer;
= 0.244 seconds
Explanation;
500 rpm is equivalent to; 1500 × 2π radians per minute
= 9424.8 rad/minute
To get revolutions per second we divide by 60
= 9424.8/60
= 157.08 radians per second.
Then we divide by 64.3 rad/s^2 to get time;
= 157.08/64.3
= 0.244 seconds.
Explanation:
Natural selection is the process through which populations of living organisms adapt and change. Individuals in a population are naturally variable, meaning that they are all different in some ways. This variation means that some individuals have traits better suited to the environment than others
Answer:

Explanation:
From the question we are told that:
Length 
Mass 
Angular Velocity 
Generally the equation for Kinetic energy K.E is mathematically given by
