Answer:
option A
Explanation:
A soccer field is about 100 meters of length, with the other instruments is possible to make the measure, but it will be very complex and it will take time. Therefore with the 50-m tape, the student will need only two measures.
Answer:
1. It may change the direction of an object in motion.
2. It may cause change in velocity of an object in motion.
Explanation:
1.It may change the direction of an object in motion.
When an object is in motion,an applied force on that object may change its direction.
For example, a sailboat moving eastward, can suddenly change its direction by interaction of a storm wind blowing form the south.
2. It may cause change in velocity of an object in motion .
A force applied to an object in motion can increase or decrease its speed. When the force is applied to the object in motion in the direction of that object, its velocity may increase.
On the other hand, when the force is applied in the opposite direction to the object in motion, its velocity may reduce.
Answer:
The acceleration of a point on the wheel is 11.43 m/s² acting radially inward.
Explanation:
The centripetal acceleration acts on a body when it is performing a circular motion.
Here, a point on the bicycle is performing circular motion as the rotation of the wheel produces a circular motion.
The centripetal acceleration of a point moving with a velocity
and at a distance of
from the axis of rotation is given as:

Here, 
∴ 
Therefore, the acceleration of a point on the wheel is 11.43 m/s² acting radially inward.
Answer:

Explanation:
Given:
- mass of water,

- initial temperature of water,

- initial temperature of pan,

- mass of pan,

- mass of water evapourated,

- specific heat of water,

- specific heat of aluminium pan,

- latent heat of vapourization,

<u>Using the equation of heat:</u>
<em>Here, initially certain mass of water is vapourised first and then the remaining mass of water comes in thermal equilibrium with the pan.</em>


