ATTIVITÀ A sorpasso
** Una motocicletta che viaggia a una velocità di 128 km/h
sorpassa un'automobile ferma. L'automobile parte dopo
un tempo di reazione di 1,25 s e comincia ad accelerare
uniformemente con un'accelerazione di 2,05 m/s2. Dopo
quanto tempo e a che distanza dal punto in cui era ferma,
l'auto raggiunge la moto?
[35,9 s; 1324 m]
10

Aparticle with mass 1.81×10−3 kg and a charge of 1.22×10−8 c has, at a given instant, a velocity v⃗ =(3.00×104m/s)j^. what are the magnitude and direction of the particle’s acceleration produced by a uniform magnetic field b⃗ =(1.63t)i^+(0.980t)j^?

Boxing gloves are padded to lessen the force of a blow. (a) calculate the force exerted by a boxing glove on an opponent’s face, if the glove and face compress 7.50 cm during a blow in which the 7.00-kg arm and glove are brought to rest from an initial speed of 10.0 m/s. (b) calculate the force exerted by an identical blow in the gory old days when no gloves were used and the knuckles and face would compress only 2.00 cm. (c) discuss the magnitude of the force with glove on. does it seem high enough to cause damage even though it is lower than the force with no glove?

If a star is moving toward earth, it is