The letter that answers this question correctly is E .
Explanation:
m = kg. v=m/s. g=m/s^2. h= m
>>1/2mv^2=mgh
>>1/2mv^2=mgh>> kg*(m/s)^2= kg*m/s^2*m
>>1/2mv^2=mgh>> kg*(m/s)^2= kg*m/s^2*m>>kg m^2/s^2=kg m^2/s^2 the fraction 1/2 won't be able to make any changes to to the dimensional expression of energy i.e half of energy is still energy therefore you can neglect the number .
<u>>>kg m^2/s^2=kg m^2/s^2</u><u> </u>
<u>></u><u>></u><u>J</u>= J
To solve this problem it is necessary to apply the equations related to the description of the tangential and angular movement.
The displacement where the speed and acceleration is related is given by the equation:
Where
Initial velocity (0 because start from rest)
t = time
a = Acceleration
We have angular acceleration but not tangential acceleration. Tangential acceleration can be obtained through the relationship
And we have also that the displacement is
Now replacing,
Therefore will take the cord to unwind around 10s
Answer:
1800 seconds
Explanation:
Given,
Distance ( d ) = 18 km
Velocity ( v ) = 10 m/s
To find : Time ( t ) = ?
Distance in km need to be converted to m.
1 km = 1000 m
18 km
= 18 x 1000
= 18000 m
So,
d = 18000 m
Formula : -
v = d / t
t = d / v
= 18000 / 10
t = 1800 seconds.
Therefore,
1800 seconds long, it will take to cover a distance of 18 km.
The correct answer is b changing tides
