Answer:
3. both are true.
Explanation:
Energy increses with decrease in wavelenght.
For photoemission to occur, a threshold energy barrier must be broken.
Higher energy means more electrons will be emmited.
The electrons emmited will posses energy that is less than the incident energy by the value of the threshold energy.
So the higher the energy, the higher the energy possessed by the electrons.
Answer:
d. All of these
Explanation:
work is said to be done when a force is applied to an object through a certain distance. the SI unit of workdone is joules or newton per meter
mathematically
workdone = force x distance.
from the answers, work is being done because there is force applied in a certain distance.
- from wagon is used to carry vegetables from a garden.
- pulley is used to get water from a well.
- hammer is used to remove a nail from a wall.
the earth exerts a gravitational force
Answer:
Explanation:
The mass of the car doesn't matter because On a flat curve the mass of the car does not affect the speed at which it can stay on the curve. You would need the mass if you were solving the the centripetal force acting on the car, but not the acceleration.
and filling in
and we need 2 significant digits in our answer. That means that
a = 1.5 m/sec²