(HELP ASAP) A student’s cell phone battery is almost dead, and she plugs it into an electrical outlet to charge. As it charges, she notices a light is glowing red to indicate that it is charging; she also notices that the phone is warm. After the battery has been fully charged and the student unplugs her cell phone, the phone vibrates when a message arrives.

Explanation:

The total energy of the system remains conserved. It just converts from one form of energy to another.

The battery of the cell phone contains chemicals. As the electricity is passed through the cell phone, the electrical energy is converted to chemical energy. As she notices that the phone is warm and after the battery has been fully charged and the student unplugs her cell phone, the phone vibrates when a message arrives, this shows the conversion of chemical energy to mechanical energy, thermal energy etc.

Hence, we can say that the correct option is (b).

think its the third option

force is based upon mass and acceleration.the statement is not always true.

it can be explained from newton's second law of motion.

as per newton's second law of motion the rate of change of momentum is directly proportional to the applied force and takes place along the direction of force.

mathematically it can be written as -

                                              ⇒      

here   k is the proportionality constant whose value is 1.

                                                            [a is the acceleration=dv/dt]

hence we see that force not only depends on mass and acceleration but also on velocity and rate of change of mass. force f will depend on mass and acceleration only when mass is constant.

hence the statement that force is based upon mass and acceleration is false.