Answer:
speed=330m/s
Explanation:
the speed of wave is given as
speed(meter per second) =frequency(hertz) * wavelength(meters)
so using the above formula we substitute the figures given in the question in the formula we get
speed = 0.4*825
speed =330m/s
note m/s is the si unit for speed which is read as meter per second
therefore speed =330m/s
As the speed is a scalar quantity as it has the only magnitude in it. Therefore, the average speed is also stated as a scalar quantity.
Hence, the correct answer is (B)
Answer:
Explanation:
Both the pizza rolls are on two circular paths having different radii because one of them is on the rim and another is near the central axis. Their angular velocity are equal . That means they rotate by same angle in equal period of time. So in Δt they make equal angles at the centre. Hence their angular displacements are equal.
But length of arc made by them in equal interval of time that is Δt are different. Ir is so because their speed are different . Speed v and angular speed ω are related to each other as follows.
v = ω r .
So for objects in motion on circular paths having different radii , v are different even if their ω are same.
length of arc l = v Δt
So length of arc will be proportional to their v which will be proportional to r if their ω are same .
Hence length of arc will be proportional to radius of circular path, ie their distance from the centre .
Answer:
Silica
Explanation:
The most commonly used abrasives are hydrated silica (softened silica), calcium carbonate (also known as chalk), and sodium bicarbonate (baking soda).
