If the bubble travels 10 meters per second and it takes 10 seconds, then just multiply the distance per second by the total seconds to get the total depth.
10 • 10 = 100
The lake is 100 meters deep.
Think of it this way to clarify the answer:
It takes a bubble traveling at a speed of 10 meters per second 10 seconds to travel 100 meters.
Answer: Acceleration due to gravity
Explanation: Force, F = mg, is a vector quantity because the acceleration due to gravity, g, is a vector quantity. Explanation: F = mg Where m is the mass (in kilograms) of the object in question and g is the acceleration due to gravity. Mass is a scalar quantity; mass has no dependence on direction whatsoever.
Answer:
is the initial velocity of tossing the apple.
the apple should be tossed after 
Explanation:
Given:
- velocity of arrow in projectile,

- angle of projectile from the horizontal,

- distance of the point of tossing up of an apple,

<u>Now the horizontal component of velocity:</u>



<u>The vertical component of the velocity:</u>



<u>Time taken by the projectile to travel the distance of 30 m:</u>



<u>Vertical position of the projectile at this time:</u>



<u>Now this height should be the maximum height of the tossed apple where its velocity becomes zero.</u>


is the initial velocity of tossing the apple.
<u>Time taken to reach this height:</u>



<u>We observe that </u>
<u> hence the time after the launch of the projectile after which the apple should be tossed is:</u>


