Answer:
Energy conservation.
Explanation:
The 1st Law of Thermodynamics is a statement about energy conservation. It states that
, which means that if we <u>substract the work W done</u> by the system to the <u>heat Q given</u> to the system we get the <u>change in the internal energy</u>
, so any excess in energy given to the system appears as internal energy, stating that energy is conserved.
1.cool down
2.activity log
3.specific warm up
4.activities of daily living
5.planned exercise
6.general warm up
Answer:
The time taken by the duck to cross the lake is, t= 4 s
Explanation:
Given data,
The initial speed of the ducks, u = 3 m/s
The final speed of the ducks, v = 7 m/s
The acceleration of the duck, a = 1 m/s²
The formula for the acceleration is,
a = (v - u) / t
∴ t = (v - u) / a
Substituting the given values in the above equation,
t = (7 - 3) / 1
= 4 s
Hence, the time taken by the duck to cross the lake is, t= 4 s
Answer:
v = 7.4 m/s
Explanation:
Given that,
Mass if a volleyball, m = 5 kg
The ball reaches a height of 2.8 m
We need to find how fast the ball is going as it bumped into the air. Ket the velocity is v. Using the conservation of energy to find it as follows :
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So, the required speed is 7.4 m/s. Hence, the correct option is (b).
Answer:
Option (c).
Explanation:
An object when when projected at an angle, will have some horizontal velocity and vertical velocity such that,

is the angle of projection
The horizontal component of the projectile remains the same because there is no horizontal motion. Vertical component changes at every point.
As a projectile falls, vertical velocity increases in magnitude, horizontal velocity stays the same
.