Question

please solve the fast

Answer 1

Solution -
The body is in three stages (1) uniform acceleration. (2) uniform velocity. (3) uniform retardation(negative acceleration)

(1) In uniform acceleration
a = 2 m/s²
t = 10 s
u = 0
v = ?
v = u + at
$v = 0 + 2 \times 10 = 20$
v = 20 m/s

(2) In uniform velocity
a = 0
v = 20 m/s
t = 20 s

(3) In uniform retardation
a = -2 m/s²
v = 0
u = 20 m/s
t = ?
v = u + at
$0 = 20 + ( - 2) t$
$2t = 20$
$t = 10$
t = 10 s





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