La distanza Terra-Sole è uguale a \( 1,496 \cdot 10^{11} \mathrm{~m} \). Se nel- lo spazio vuoto la luce viaggia a \( 2,998 \cdot 10^{8} \mathrm{~m} / \mathrm{s} \), quanto tempo impiega la luce del Sole a raggiungere la Terra?

3. Analyze: Friction causes work to be "wasted" as heat (which is why your hands get warm). A. Does friction waste more work on longer or shorter planes? B. How can you tell? C. Why do you think this is? [Hint: Remember the stick presses up on the item. Do your hands get warmer faster if you press them together harder as you rub?] Conjecture: Does friction cause more energy to be wasted if the object is heavier? Why? Use the Gizmo to test this. Describe your results in your notebook or on a separate sheet.

\( \left.\qquad R .3,6 \mathrm{~m} / \mathrm{s}^{2} ; 270 \mathrm{~m} / \mathrm{s}^{2} ; 1,6 \mathrm{~m} / \mathrm{s}^{2}\right] \) Determina l'accelerazione di gravita g' esercitata dalla Terra sulla Luna, sapendo che la distanza della Luna dalla Terra è 60,25 raggi terrestri e che l'accelerazione di gravità g è \( 9,8 \mathrm{~m} / \mathrm{s}^{2} \). [R. \( \left.0,27 \mathrm{~cm} / \mathrm{s}^{2}\right] \)

The bullet hits the 50 cm thick wooden board with a speed of \( 108 \mathrm{~km} / \mathrm{h} \). What is the deceleration of the bullet, if it leaves the board after 3.5 s ?

4. Conjecture: Does thiction cause more energy to be wasted if the object is heavier? Why? Use the Gizmo to test this. Describe your results in your notebook or on a separate sheet.

14. Di qué tipo de movimiento tendrá un cuerpo sometido a una fuerza resultante nula y a un momento de las fuerzas no nulo. ¿Y un cuerpo sometido a una fuerza resultante no nula?