True! In order for work to be done, a force must cause movement.
Answer:
Explanation:
Direction of velocity of electromagnetic wave is given by the formula
E = E j ( vector form )
B = - Bi ( vector form )
Direction of velocity = direction of vector E X B
= E X B
= E j x -Bi
= - EB -k
v = EBk
So the direction of velocity will be along z direction.
Answer:
We can conclude by saying that in the beginning current will increase but after sometime, it becomes saturated.
Explanation:
Note: No information on change in number of electron generated.
Since there is a collision, the electrons emitted will not reach the collector at same time. As the voltage is increased, the the speed with which the electrons will reach the collector starts to increase. Due to this, electric current will first increases till all the emitted electrons reach the collector. Since we are not provided with the information that number of electrons generated are changing, after increasing voltage current will increase for some time and then reaches a saturated state.
We can conclude by saying that in the beginning current will increase but after sometime it becomes saturated.
Answer:
6.85 m/s
Explanation:
We can solve the problem by using the law of conservation of momentum.
In fact, since there are no external forces acting, the total momentum before and after must be conserved. So we can write:
where
is the initial mass of the car
is the initial speed of the car
is the mass of the car after the load of gravel is dropped
v2 is the final speed of the car
Solving for v2, we find
