Strength of Materials
The effort required to lift a load W on a screw jack with helix angle a and angle of friction<="" div="">

Wtan(a-<)>)
Wtan(a + <)>)
Wsin(a + <(>)
Wcos(a + )

ANSWER DOWNLOAD EXAMIANS APP

Strength of Materials
In ideal machines

mechanical advantage is greater than velocity ratio
mechanical advantage is equal to velocity ratio
mechanical advantage is unity
mechanical advantage is less than velocity ratio

ANSWER DOWNLOAD EXAMIANS APP