Heat and Mass Transfer
Metals are good conductors of heat because

Their atoms are relatively far apart
Their atoms collide frequently
They contain free electrons
They have high density

ANSWER DOWNLOAD EXAMIANS APP

Heat and Mass Transfer
The logarithmic mean temperature difference (tm) is given by (where Δt1 and Δt2 are temperature differences between the hot and cold fluids at entrance and exit)

tm = (Δt1 - Δt2)/ loge (Δt1/Δt2)
tm = loge (Δt1 - Δt2)/ Δt1/Δt2
tm = loge (Δt1/Δt2)/ (Δt1 - Δt2)
tm = tm = (Δt1 - Δt2) loge (Δt1/Δt2)

ANSWER DOWNLOAD EXAMIANS APP