D is the best answer. In many physics problems we treat an extended object as if it were a point with the same mass located at the center of mass.
Answer:
a} <u>Infrared radiant heaters.</u>
<u>b} Fan heaters.</u>
Explanation:
I hope this is okay, should I give more.
Answer:
20 N
Explanation:
In air, the normal force is equal to the weight.
∑F = ma
N − mg = 0
N = mg
Submerged in water, the normal force is equal to the weight minus the buoyant force:
∑F = ma
B + N − mg = 0
N = mg − B
Plugging in values:
80 N = 100 N − B
B = 20 N