Answer:
Explanation:
When the positively charged half shell is brought in contact with the electroscope, its needle deflects due to charge present on the shell.
When the negatively charged half shell is brought in contact with the positively charged shell , the positive and negative charge present on each shell neutralises each other .So both the shells lose their charges .The positive half shell also loses all its charges
When we separate the half shells , there will be no deflection in the electroscope because both the shell have already lost their charges and they have become neutral bodies . So they will not be able to produce any deflection in the electroscope.
As we know that reaction time will be

so the distance moved by car in reaction time



now the distance remain after that from intersection point is given by

So our distance from the intersection will be 100 m when we apply brakes
now this distance should be covered till the car will stop
so here we will have


now from kinematics equation we will have



so the acceleration required by brakes is -2 m/s/s
Now total time taken to stop the car after applying brakes will be given as



total time to stop the car is given as


Actually Welcome to the Concept of the Force and Power.
Since, according to the Newton's law,
Force = mass * Acceleration.
hence, here
Force = 142 N, accelration = 22.75 m/s2
hence, mass = 142/22.75
===> Mass = 6.24 Kg
hence the mass of the shot is 6.24 Kg
<h2>
Answer: B. Gravitational potential energy </h2>
Explanation:
<em>The gravitational potential energy is the energy that a body or object possesses, due to its position in a gravitational field.
</em>
That is why this energy depends on the relative height of an object with respect to some point of reference and associated with the gravitational force.
In the case of the <u>Earth</u>, in which <u>the gravitational field is considered constant</u>, the value of the gravitational potential energy
will be:
Where
is the mass of the object,
the acceleration due gravity and
the height of the object.
As we can see, the value of
is directly proportional to the height.
Answer:
Er = 108 [J]
Explanation:
To solve this problem we must understand that the total energy is 200 [J]. Of this energy 44 [J] are lost in sound and 48 [J] are lost in heat. In such a way that these energy values must be subtracted from the total of the kinetic energy.
200 - 44 - 48 = Er
Where:
Er = remaining energy [J]
Er = 108 [J]