Answer:
True
Explanation:
Cohesive forces are forces that exist between the molecules of a substance of the same material while adhesive forces are forces that exists between the molecules of the substances of different materials.
This is responsible for the nature of menisci formed by different liquids when they are filled into containers or glass tubes.
If the cohesive forces of the liquid molecules are stronger than the adhesive forces between the liquid molecules and the glass material, a convex meniscus will be formed. This means that the edges of the liquid touching the glasses are lower than the surface at the centre. The meniscus formed by mercury in a glass tube is an example of this.
However, If the cohesive forces of the liquid molecules are weaker than the adhesive forces between the liquid molecules and the glass material, a concave meniscus will be formed. This means that the edges of the liquid touching the glasses are higher than the surface at the centre. The meniscus formed by water in a glass tube is an example of this.
Please view the attached diagram:
Please note: I got the diagram online, it was not drawn by me. I Just needed to quickly get something to illustrate my explanations. Thanks.
Answer:
The centripetal force acting on the child is 39400.56 N.
Explanation:
Given:
Mass of the child is,
Radius of the barrel is,
Number of revolutions are,
Time taken for 10 revolutions is,
Therefore, the time period of the child is given as:
Now, angular velocity is related to time period as:
Now, centripetal force acting on the child is given as:
Therefore, the centripetal force acting on the child is 39400.56 N.
Answer:
The other angle is 30 degrees.
Explanation:
The range of projectile is given by :
Here,
u is the speed of launch of projectile
Here,
We need to find the other launch angle when the projectile have the same range, such that,
So, the other angle is 30 degrees. Hence, this is the required solution.