Question

The distance and displacement of the particle from0 to 15 second is
a. 100m, 50mb) 100m, 100m C) 100m, 200m d) 100m, o
In which time interval the particle is speeding up?
a 0 to 10s
b) 10 to 15s C) 15 to 20s
d) 10 to 20s
In which time interval the particle is moving with zero acceleration?
a. O to 5s
b) 5 to 10s c) 10 to 155
d) 15 to 20s
In which time interval the particle is moving with negative acceleration?
a. 5 to 10 s
b) 10 to 15s c) 15 to 20 s
d) O to s​

Answer 1

Answer:

A = (v - u)/t

= (0 - u)/t

= -u / (5 s)

S = ut + 0.5at²

100 = 5u + (0.5 × [-u / (5 s)] × (5 s)²)

100 = 5u - 2.5u

100 = 2.5u

u = 40 m/s

If u = 40 m/s then

a = -u / (5 s)

= -(40 m/s) / (5 s)

= -8 m/s²

Displacement covered in 10 seconds

S = ut + 0.5at²

= (40 m/s × 10 s) + [0.5 × (-8 m/s² × (10 s)²]

= 0 m

Particle travelled 100 m in first 5 seconds and in next 5 seconds it travels 100 m back to initial position. Hence we got Displacement after 10 seconds equal to zero.