QUESTION 5: HYDRAULICS 5.1 The data below refer to a single-acting hydraulic press. Diameter of the ram piston \( \quad=450 \mathrm{~mm} \) Diameter of the plunger piston \( \quad=100 \mathrm{~mm} \) Stroke length of the plunger \( =120 \mathrm{~mm} \) Mechanical advantage of the plunger \( =20 \)

51. Un blocco di 3,2 kg è appeso mediante una molla al sof- fitto. L'energia potenziale elastica del sistema bloc- co-molla è \( 1,8 \mathrm{~J} \). Calcola l'energia potenziale elastica del sistema quan- do il blocco è sostituito con un blocco di \( 5,0 \mathrm{~kg} .[4,4 \mathrm{~J}] \)

Question 1: Choose the correct answer from the options provided: 1) A body of weight 14 dyne was put on a smooth plane inclined to the horizontal by angle of measure \( \theta \) and kept equilibrium by a force in direction of greatest slope up it's magnitude is 7 dyne thea: \( m \). \( (\theta)=\ldots \) \( \begin{array}{llll}\text { a. } 60 & \text { b. } 45 & \text { c. } 30 & \text { d. } 75\end{array} \)

4. Mit einem Tauchsieder werden 300 g Wasser in 30 s um \( 6,5^{\circ} \mathrm{C} \) erwärmt. a) Um wieviel Grad werden in der gleichen Zeit 100 g Wasser erwärmt? b) Wieviel Gramm Wasser können in der gleichen Zeit um \( 10^{\circ} \mathrm{C} \) erwärmt werden? 5. Das Gewicht von Schmucksteinen wird in Karat angegeben. Der größte jemals gefundene Smaragd wog 2680 Karat, das sind 536 g . a) Wie viel Gramm wiegt der größte geschliffene Smaragd von 1300 Karat? b) Um wie viel Prozent ist er leichter als der ungeschliffene Stein?

6) A body of weight 16 N . on horizontal rough plane. the static coefficient of friction between the plane and the body is \( \frac{3}{4} \), if a force of magnitude 40 N . acts on the body, then: the body is .................... \( \begin{array}{ll}\text { a. At rest, and about to move. } & \text { c. moving. } \\ \text { b. At rest, put not about to move. } & \text { d. moving, about to be at stop. }\end{array} \)

5) The angle of friction between a body and rough horizontal surface is \( 60^{\circ} \), and the normal reaction is of 75 N ., then: the resultant reaction is \( \ldots \ldots . \mathrm{N} \) \( \begin{array}{llll}\text { a. } 60 & \text { b. } 30 & \text { c. } 120 & \text { d. } 150\end{array} \)