Answer:
The maximum speed will be 26.475 m/sec
Explanation:
We have given mass of the toy m = 0.50 kg
radius of the light string r = 1 m
Tension on the string T = 350 N
We have to find the maximum speed without breaking the string
For without breaking the string tension must be equal to the centripetal force
So 
So 

v = 26.475 m /sec
So the maximum speed will be 26.475 m/sec
Answer:2800000j
Explanation:
For us to know the kinetic energy of the vehicle,
Where m is the mass
And v is the velocity
Then, K.E=1/2mv^2
While, K.E=1/2×3500×40^2
Therefore, our answer will now be
K.E=2800000j
-- If acceleration and velocity are in the same direction,
then the object is speeding up.
-- If acceleration and velocity are in opposite directions,
then the object is slowing down.
-- If acceleration is perpendicular to velocity, then the object
is moving on a circular curve at constant speed.