Question

B-1:

Answer 1

Answer:

(a) t = 1.67 s

(b) s₂ = 45 m

Explanation:

Here, we use the formula:

s = vt

FOR Seth:

s₁ = v₁t₁

where,

s₁ = distance covered by Seth

v₁ = speed of Seth = 9 m/s

t₁ = time taken by Seth

FOR Mack:

s₂ = v₂t₂

where,

s₂ = distance covered by Mack

v₂ = speed of Mack = 27 m/s

t₂ = time taken by Mack

since, initially Mack is 30 m behind Seth. Therefore,

(a)

s₂ = s₁ + 30 m

using formulae:

v₂t₂ = v₁t₁ + 30 m

but, the time of catching is same for both (t₁ = t₂ = t)

v₂t = v₁t + 30 m

using values:

(27 m/s)t - (9 m/s)t = 30 m

t = (30 m)/(18 m/s)

t = 1.67 s

(b)

s₂ = v₂t

using values:

s₂ = (27 m/s)(1.67 s)

s₂ = 45 m