v₀ = initial velocity of the mobile = 10 m/s
v = final velocity of the mobile = 20 m/s
a = acceleration of the mobile = 5 m/s²
d = distance traveled during this operation = ?
Using the kinematics equation
v² = v²₀ + 2 a d
inserting the above values in the equation
20² = 10² + 2 (5) d
400 = 100 + 10 d
subtracting 100 both side
400 - 100 = 100 - 100 + 10 d
300 = 10 d
dividing both side by 10
300/10 = 10 d/10
d = 30 m
hence mobile travels 30 m.