Answer:
A) and B) are correct.
Explanation:
If the object is at rest, it means that no net force is exerted on it.
As the object experiences a downward gravitational force from Earth, in order to be at rest, it must experience an upward force with the same magnitude as the gravitational force on the object.
This force is supplied by the normal force, which can adopt any value in order to meet the condition imposed by Newton´s 2nd Law, and is always perpendicular to the surface on which the object is placed (in this case, the ground).
At a molecular level, this normal force is supplied by the bonded molecules of the ground that behave like small springs being compressed by the molecules of the object, exerting an upward restoring force upward on them.
So, the statements A) and B) are true.
If the ice absorbed 350,000 joules in 5 minutes, then it absorbed energy
at the rate of
(350,000 joules) / (5 x 60 seconds) =<em> 1,166-2/3 watts</em> .
Surely the ice cube didn't absorb every joule delivered to the cooking chamber,
so the microwave oven's cooking power had to be significantly more than that.
Correct answer choice is:
D. A frequency higher than the original frequency.
Explanation:
This is a true case of Doppler's effect. The Doppler effect can be defined as the effect originated by a traveling source of waves in which there is a visible higher variation in pulse for observers towards what the source is progressing and a visible descending shift in rate for observers from what the source is dropping.
Answer:

Explanation:
Given:
- mass of steam,

- temperature of steam,

- temperature of resultant water,

We have,
- latent heat of vapourization of water,

- specific heat capacity of water,

<em>When we cool the steam of 100°C then firstly it loses its latent heat to convert into water of 100°C and the further cools the water.</em>
<u>Now the heat removed from steam to achieve the final state of water:</u>




Im not really sure about this im stuck to