Answer:
Distance covered by the sound in air is 800 meter and the time taken by the sound in water for the same distance is 0.5 seconds.
Explanation:
Given:
Speed of sound in air = 320 m/s
Speed of sound in water = 1600 m/s
Time taken to reach certain distance in air = 2.5 sec
a.
We have to find the distance traveled by sound in air.
Distance = Product of speed and time.
⇒ 
⇒ 
⇒ 
meters.
b.
Now we have to find how much time the sound will take to travel in water.
⇒ Time = Ratio of distance and speed
⇒ 
⇒ 
<em> ...distance = 800 m and speed = 1600 m/s</em>
⇒ 
⇒ 
seconds.
Distance covered by the sound in air is 800 meter and the time taken by the sound in water for the same distance is 0.5 seconds.
Answer:
A. The particle model, because only high-energy frequencies of light can remove electrons .
Explanation:
Each photon of blue light has higher energy than each photon of red light has . So when each photon strikes each electron , it gets ejected . But the photon of red light has not sufficient energy to eject electron . Once the photon of red light strikes the electron , the energy is wasted off . Energy of photon can not be accumulated . Thus photon behaves like particle .
The correct answer to the question is False i.e the tendency of an object in motion to remain in motion is not called the orbital speed.
EXPLANATION:
Before going to answer this question, first we have to understand Newton's first laws of motion.
As per Newton's first laws of motion, every body continues to be in state of rest or of uniform motion in a straight line unless and until it is compelled by some external unbalanced forces.
Hence, as long as no unbalanced force is acting on a moving object, it will be in motion. This tendency of a moving object to be in motion is called inertia of motion of the body.
Inertia of motion is the property of the body by virtue of which a moving body always tries to be in motion.
Hence, the tendency of an object in motion to remain in motion is not called as the orbital speed.
