TECNOLOGIA s La distanza di arresto di un veicolo in frenata dipende dal quadrato della sua velocità. A \( 10 \mathrm{~m} / \mathrm{s} \) la distanza di arresto è di circa 7 m . Scrivi la legge che lega la distanza di arresto alla velocità. Costruisci una tabella distanza-velocità e rappresenta i dati in un grafico.

body placed on a rough horizontal level \( W=75 \mathrm{~N} \) horizontal force affected 50 N Makes it about to move en the coefficient of friction equals \( \begin{array}{llll}\text { 1) } \frac{1}{3} & \text { 2) } \frac{2}{3} & \text { 3) } \frac{3}{4} & \text { 4) } \frac{1}{4}\end{array} \)

b. Un moteur consomme \( x \) litres d'essence de masse volumique \( \rho \) et de pouvoir énergétique en \( h \) heures. 1. Quelle est la puissance \( P \) de ce moteur? 2. Trouverais-tu une valeur plus faible ou plus élevée si tu tenais compte des pertes d'énerg c. Un thermoplongeur de puissance \( P \) permet de chauffer une masse \( m \) de liquide de chaleul massique c de la température \( T_{1} \) à \( T_{2} \) en un temps \( t \). 1. Exprime la masse de liquide chauffée par ce thermoplongeur. 2. Exprime la température \( T_{2} \) du liquide.

3) if \( \overrightarrow{F_{1}}, \overrightarrow{F_{2}}, \overrightarrow{F_{3}} \) are 3 forces that meets at a point and equilibrium: then the resultant of \( \overrightarrow{F_{1}}, \overrightarrow{F_{2}} \) equal : \( \begin{array}{lll}\text { 1) } \overrightarrow{F_{1}}, & \text { 2) } \overrightarrow{F_{1}}+\overrightarrow{F_{2}} & \text { 3) } \overrightarrow{F_{3}}\end{array} \)

QUESTION 1: EPICYCLIC GEAR AND GEAR TRAINS An epicyclic gear train has a sun wheel with 24 teeth, and two planetary wheels of 46 teeth each, The latter mesh with the internal teeth of a fixed annulus with 116 teeth. The input shaft, carrying the sun wheel, transmits \( 4,5 \mathrm{~kW} \) at \( 280 \mathrm{r} / \mathrm{min} \). The output shaft is connected to an arm L that carries the planetary wheels. Calculate the speed of the output shaft.

4. When you descend in a plane, your ears pop. Is air moving into your ears or out of them when they pop? 5. Explain why a balloon gets bigger as you put more molecules of gas into it at a constant temperature.