Answer:
B. The number of wave cycles that pass through a specific point within a given time period.
The elements that is very good in
electrical conductivity are gold and copper: elements that is amphoteric are
copper, zinc, tin, lead, aluminum and beryllium: elements that is gaseous at
room temperature are hydrogen, nitrogen, oxygen, fluorine and chlorine: elements
that is solid at room temperature are all metal except mercury and perhaps some
unseen radioactive elements. Lastly, elements that is brittle are hydrogen,
carbon, nitrogen, oxygen, phosphorus, sulfur and selenium
Answer:
An opaque object with many closely spaced slits
Explanation:
Diffraction grating is an opaque object which will have many close slits on it
Each slit will allow the light wave pass through it which incident on it.
So here each slit will behave like a secondary source which will transmit the light and the superposition of light is then observed on the screen
These large number of slits on the object is combined known as diffraction grating.
By the superposition of waves due to grating we will have pattern of maximum and minimum intensity on the screen and this intensity if highest at the mid point of screen and then decreases as we move away
Answer:
20 m/s
Explanation:
The stored energy is transformed to kinetic energy and since kinetic energy is given by
where m is the mass of arrow in Kg and v is the velocity of the arrow in m/s. From the principle of energy, all the energy is transformed to KE.
KE= Energy stored in bow
Changing mass from 50 g to Kg we divide by 1000 hence m=50/1000=0.05 Kg
Substituting 0.05 Kg for m and 10 J for KE then we have
0.5\times 0.05\times v^{2}=10 J
Making v the subject of the formula then
Therefore, the velocity is equivalent to 20 m/s
