4. a) Expliquer comment connecter des piles de 1,5 V afin d'obtenir une différence de potentiel totale de 9 V. b) Qu'arrivera-t-il au potentiel électrique de la batterie de 9 V si une des piles est inversée.

15. one purpose of the tread pattern on a tire is to a reduce tire wear. b. reduce traction c. allow water to flow away from the tire. d. look impressive.

It's a snowy day and you're pulling a friend along a level road on a sled. you've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. you've been walking at a steady 1.5m/s, and the rope pulls up on the sled at a 32 ∘ angle. you estimate that the mass of the sled, with your friend on it, is 65 kg and that you're pulling with a force of 80 n .

Heterogeneous mixture with larger particles that never settle is