Select the correct answer.
when a cup is placed on a table, which force prevents the cup from falling to the ground?
a.
gravitational force
b. normal force
c.
resistance force
d.
tension force

B. Normal Force

Explanation:

Gravitational force is what keeps us from floating off while normal force is the support force exerted on an object that's in contact with another stable object. So if the cup is resting on a table, then the table is exerting an upward force (normal force) on the cup in order to support the weight of the book.

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it

we're given that v₀ = 0 and a = 5.4 m/s². therefore, since v = at + v₀ for constant acceleration the equation for velocity is

after 28s,

m/s

which i would round to 150 m/s as my final answer