Answer:
Yes it is possible to control to some extent.
Explanation:
In general there are two types of magnets : permanent and temporary (electromagnets).
Electromagnets can be controlled since it basically depends on electricity. By switching on and off the electric supply the magnets also can be switched on and off respectively. We can also control the intensity of magnetic power.
On the other hand permanent magnet cannot be switched on and off but the magnetic properties can be altered event to an extent when it loses all its magnetic properties. It can be caused by high temperature, physical impact and also exposure to other magnetic fields. For every element there is a point of temperature called curie temperature above which the permanent magnet loses its magnetic properties. This can be brought back again by induced magnetism. The only issue is that induced magnetism work in most cases but not in all.
Answer:
0.775 m
Explanation:
As the car collides with the bumper, all the kinetic energy of the car (K) is converted into elastic potential energy of the bumper (U):

where we have
is the spring constant of the bumper
x is the maximum compression of the bumper
is the mass of the car
is the speed of the car
Solving for x, we find the maximum compression of the spring:

As we know that power is defined as rate of work done
so we will have

so in order to increase the power as per above formula we know that either we need to increase the work or we need to decrease the time to complete that work
So here the correct answer will be
increase the work being done or decrease the time in which the work is completed.
Answer:
B. Observation
Explanation:
Using a thermometer to read the temperature of a solution is tantamount to the making an observation.
Observation are recorded using our senses of sight, taste, earing, feeling etc or by the use of instrument.
- Through observation, data is usually collected to make inferences about an experiment.
- An observation leads to the formulation of a hypothesis which is scientific guess that leads to experimental designs.
- Conclusions are drawn from the information of data obtained from an experiment.