Answer:
0.211 kg
Explanation:
specific heat capacity of copper = 385 J/Kgk
heat loss by copper = mcθ = 3.8 × (8 - 84 ) × 385 = - 111188 J
heat needed to raise the temperature of water from 0°C to 8°C
= mcθ = 1.2 kg × 4180 × ( 8 - 0) = 40128 J
111188 J - 40128 J = 71060
71060 = ml
71060 / 336000 = mass of ice where latent heat of fusion = 3.36 × 10⁵JKg⁻¹
m = 0.211 kg
Answer:
I. They come from sources across space
II. They travel in a straight line from their source.
III. They can be reflected by some types of material.
Explanation:
Light wave can be defined as an electromagnetic wave that do not require a medium of propagation for it to travel through a vacuum of space where no particles exist.
The following statements about light waves are true;
I. They come from sources across space.
II. They travel in a straight line from their source.
III. They can be reflected by some types of material. reflection occurs when a ray of light or wavefronts bounces off a smooth surface. Thus, when light hit a surface, it bounces back to the medium from which it was originally propagated with.
However, light waves cannot travel through all type of material except materials that are transparent or translucent but not opaque.
Answer:
Explanation:
The condition that the sphere completes the loop is that it doesn't fall off at the top. In order to do that, the sphere has to have enough velocity to beat the centripetal acceleration.
The forces acting on the sphere at the top of the loop:
1- Weight of the sphere to the downwards direction.
2- The normal force to the downwards direction.
So Newton's Second Law gives the following equation
At the minimum velocity, which corresponds to minimum height 'h', the normal force is equal to zero. That means, if the sphere moves any less than the minimum velocity, its weight will be greater than the centripetal force, hence it will fall off.
Therefore,
Now, we can use the conservation of energy to find the minimum height.
Answer:
Positively charged particles in atoms are D. Protons
Explanation:
Negative = Electrons
Neutral = Neutron
Positive = Proton
Answer:
The distance to the wall does not matter.
Explanation:
According to newton's third law, if you exert a force on the tennis ball to propel it northwards, it will exert equal and opposite force on you to propel you southwards. Therefore, how much you accelerate only depends on how fast you through the balls. And once a ball has left the system<em> ( consisting of you and the ball)</em>, it can no longer have an effect on you, so it doesn't matter whether the ball hits a wall nearby or the one millions of miles away.
<em>P.S: all of this is true assuming the balls don't bounce back from the wall and hit you in the face, which would surely give you additional southward acceleration, but it wouldn't be such a pleasant experience! </em>