4% of 110 is 4.4. So the possible range of speeds is the interval from 110-4.4 till 110+4.4.
105.6 till 114.4
Give u = start velocity
v = end velocity
v = u + at
50 = 400 + a*30
30a = -350
a = -116.67 m/
**Why the accecleration is negative number**
Because displacement, velocity, and acceleration are VECTOR QUANTITIES.
Vector Quantity must have direction.
You have to decrease the length of the pendulum by 4 times in order to make the clock go 2 times faster
A - the amount of time needed to travel the distance
The formula for speed is distance/time and the unit is m/s. Therefore you divide the distance travelled by the time it took to travel it.
It would most likely be answer B considering the other ones don’t make sense in this question