Answer:
0.8%
Explanation:
We are given;
Number of oscillations; n = 20
Time taken; t = 25 s
Formula for period of oscillation;
T = t/n = 25/20 = 1.25 s
We are told that the least count is 0.2 s. Thus, error is; ΔT = 0.2 s
percentage error in the measurement of time is given by;
(0.2/(20 × 1.25)) × 100% = 0.8%
Answer:
Approximately
. (Assuming that
, and that the tabletop is level.)
Explanation:
Weight of the book:
.
If the tabletop is level, the normal force on the book will be equal (in magnitude) to weight of the book. Hence,
.
As a side note, the
and
on this book are not equal- these two forces are equal in size but point in the opposite directions.
When the book is moving, the friction
on it will be equal to
, the coefficient of kinetic friction, times
, the normal force that's acting on it.
That is:
.
Friction acts in the opposite direction of the object's motion. The friction here should act in the opposite direction of that
applied force. The net force on the book shall be:
.
Apply Newton's Second Law to find the acceleration of this book:
.
Answer:c-The gravitational effect when spacecraft flies close to the asteriod
Explanation:
Gravitational effect on the spacecraft gives an estimate that how big is the asteroid by experiencing its gravitational pull.
The amount of extra thrust required to maintain the trajectory of the spacecraft during its motion hints at the scientist about the size of the asteroid.
Gravitational pull is directly proportional to the mass of object so greater the mass, greater will be the pull.
Here we will the speed of seagull which is v = 9 m/s
this is the speed of seagull when there is no effect of wind on it
now in part a)
if effect of wind is in opposite direction then it travels 6 km in 20 min
so the average speed is given by the ratio of total distance and total time


now since effect of wind is in opposite direction then we can say



Part b)
now if bird travels in the same direction of wind then we will have


now we can find the time to go back



Part c)
Total time of round trip when wind is present


now when there is no wind total time is given by


So due to wind time will be more