There is a threshold frequency for each metal, and only light of a frequency higher than this threshold causes electrons to be emitted from the metal surface.
Answer:
d. decreases
Explanation:
The law of conservation of momentum tells us that the sum of momenta before the collision is equal to the sum of momenta after the collision. The bag has no momentum as it falls onto the boat because its velocity is zero in the horizontal direction. But after it hits the boat, it's momentum increases while the momentum of the system remains the same. That means a component of the system must decrease somewhere else. And that component is the velocity, not the mass, of the boat.
I think it’s going to be the 2nd one
Answer:
Explanation:
Both are contact forces arising at the interface between two bodies. In the fluid this interface might be irregular, and it completely surrounds a submerged object. For a solid it is usually a single flat surface - but it can be a collection of surfaces, which do not need to be flat or regular, and which can surround the object
Upthrust occurs at a fluid-solid interface whereas normal reaction occurs at a solid-solid surface. However, it is possible to generate the same fluid-like phenomenon of upthrust by immersing a solid object in sand or small beads and agitating them to simulate the pressure of atoms. With
