Answer:a
Explanation: the plates shifts cracking making earthquakes
a) earth acts as a lange magnetic. Therefore when a magnet is hanging freely, it points towards the magnetic poles (like a compass)
b) like poles repel and unlike poles attracts. We can conclude with repulsion that poles are same
c) In our everyday experience aluminum doesn't stick to magnets. (under normal circumstances aluminum isn't visibly magnetic)
Answer:
Explanation:
a. The source of centripetal force on the car is (3) the static friction force.
b. ac = v²/R = (20²)/50 = 8 m/s²
c. Fc = m(ac) = 1500(8) = 12 kN
d. μ = Fc/N = Fc/mg = 12000 / 1500(9.8) = 0.8163... ≈ 0.82
The one that will change the velocity of a periodic wave is :
B. Changing the medium of the wave
Waves is always determined by the properties of the medium, which means that changing the medium will change the velocity of the wave
hope this helps