Explanation:
Given that,
A ball is tossed straight up with an initial speed of 30 m/s
We need to find the height it will go and the time it takes in the air.
At its maximum height, its final speed, v = 0 and it will move under the action of gravity. Using equation of motion :
v = u +at
Here, a = -g
v = u -gt
i.e. u = gt

So, the time for upward motion is 3.06 seconds. It means that it will in air for 3.06×2 = 6.12 seconds
Let d is the maximum distance covered by it.

Putting all values

Hence, it will go to a height of 45.91 m and it will in the air for 6.12 seconds.
Answer:
An external force is a force that acts on an object within the system from outside the system. This type of force is different than an internal force, which acts between two objects that are both within the system. The net external force combines these two definitions; it is the total combined external force
Explanation:
ig the answer is true
Weight will remain the same for two identical books, one lying flat and the other standing on an end.
The strain at a factor internal a liquid is at once proportional to the intensity of the factor. When an item is submerged in a liquid, the intensity of its backside from the floor of the liquid is extra than that of some other a part of the item.
Archimedes' precept is the declaration that the buoyant pressure on an item is identical to the load of the fluid displaced with the aid of using the item.
Ensure your scale is on a flat, strong and stage floor. Do now no longer use your scale on carpet. When taking measurements, stand nevertheless withinside the middle of the platform till all measurements are displayed, and if feasible do now no longer circulate your scale in-among measurements.
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A higher temperature, stiffer materials, and less dense materials increase the speed of sound.
Answer:

Explanation:
The frequency of a wave can be found using the following formula.

where <em>f</em> is the frequency, <em>v</em> is the velocity/wave speed, and λ is the wavelength.
The wavelength is 10 meters and the velocity is 200 meters per second.
- 1 m/s can also be written as 1 m*s^-1
Therefore:

Substitute the values into the formula.

Divide and note that the meters (m) will cancel each other out.


- 1 s^-1 is equal to Hertz
- Therefore, our answer of 20 s^-1 is equal to 20 Hz

The frequency of the wave is <u>20 Hertz</u>