Newton's First Law states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force.
Answer:
Explanation:
work done by applied force
= force x displacement
= 7.6 x 15 m
= 114 J .
Answer:

Explanation:
Given:
- mass of rocket,

- time of observation,

- mass lost by the rocket by expulsion of air,

- velocity of air,

<u>Now the momentum of air will be equal to the momentum of rocket in the opposite direction: </u>(Using the theory of elastic collision)



Answer:
2.48 m/s
Explanation:
We can use the kinematic equation,
s = ut +½at²
Where
s = displacement
u = initial velocity
t = time taken
a = acceleration
Using the equation in vertical direction,
321 = 0×t +½×g×t², u = 0 because initial vertical velocity is 0
We get t = 8.01 s
Using the equation in the horizontal direction,
52 = u×8.01 +½×0×(8.01)²,. a = 0 because no unbalanced force act on object in that direction
So u = 2.48 m/s
Answer:
Limewater can be used to detect carbon dioxide. If carbon dioxide is bubbled through limewater then it turns from clear to cloudy/milky in colour. This is why limewater used in a simple respirometer can show that more carbon dioxide is present in exhaled air compared to inhaled air.
Explanation: