A boy whose mass is $50\,kg$ stands on a spring balance inside a lift. The lift starts to ascent with an acceleration of $2\,m{s^{ - 2}}.$ The reading of the machine or balance $(g = 10\,m{s^{ - 2 }})$ is ........ $kg$
A boy whose mass is $50\,kg$ stands on a spring balance inside a lift. The lift starts to ascent with an acceleration of $2\,m{s^{ - 2}}.$ The reading of the machine or balance $(g = 10\,m{s^{ - 2 }})$ is ........ $kg$
$50$
$0$
$49$
$60$
A boy whose mass is $50\,kg$ stands on a spring balance inside a lift. The lift starts to ascent with an acceleration of $2\,m{s^{ - 2}}.$ The reading of the machine or balance $(g = 10\,m{s^{ - 2 }})$ is ........ $kg$
$R = m\,(g + a) = 50 \times \,(10 + 2) = 600\,N = 60\,kg\,wt$