Help needed pls and thxs

What is the charge of an atom with 21 protons and 6 electrons

Svetach [21]

Answer:

Scandium with an ion charge of +3

Explanation:

4 0

3 years ago

Read 2 more answers

Katelyn (55 kg) is practicing a drop jump in the biomechanics lab. She steps off a plyometrics box, lands on the force plate, an

suter [353]

Answer:

J = 357.5 kg*m/s

Explanation:

The impulse exerted on Katelyn when she was on the force plate, is equal to the change in her momentum, according to Newton's 2nd Law.
Assuming as the positive direction the upward direction (coincident with the positive y-axis) we can express the initial momentum as follows:

$p_{o} = m*v_{o} = 55 kg * (-3.0 m/s) (1)$

By the same token, the final momentum is as follows:

$p_{f} = m*v_{f} = 55 kg * (3.5 m/s) (2)$

As we have already said, the impulse J is just equal to the change in momentum, i.e., the difference between (2) and (1):

$J = p_{f} - p_{o} = m* (v_{f} -v_{o}) = 55 kg* (3.5m/s- (-3.0m/s)) = 357.5 kg*m/s (3)$

5 0

3 years ago

What processes most directly helps create soil from rocks

Neko [114]

The process that most directly helps create soil from rocks is Weathering.

4 0

3 years ago

Two identical metal spheres A and B are in contact. Both are initially neutral. 1.0× 10 12 electrons are added to sphere A, then

Vilka [71]

Answer:

8 x 10^-8 C on both the spheres.

Explanation:

Number of electrons added to A = 1 x 10^12

As the sphere A and B are identical to each other so the charge is shared equally.

Charge of one electron = 1.6 x 10^-19 C

Charge on A after wards

= number of electrons after wards x charge of one electron

qA = 0.5 x 10^12 x 1.6 x 10^-19 = 8 x 10^-8 C

Similarly, the charge on sphere B afterwards

= number of electrons after wards x charge of one electron

qB = 0.5 x 10^12 x 1.6 x 10^-19 = 8 x 10^-8 C

8 0

4 years ago

ou have just moved into a new apartment and are trying to arrange your bedroom. You would like to move your dresser of weight 3,

Dimas [21]

So far, since you moved into the apartment until the end of this much of the story, you haven't done ANY work on the dresser yet.

I'll admit that you pushed, groaned and grunted, sweated and strained plenty. You're physically and mentally exhausted, you're not interested in the dresser at the moment, and right now you just want to snappa cappa brew, crash on the couch, and watch cartoons on TV. But if you've done your Physics homework, you know you haven't technically done any work yet.

In Physics, "Work" is the product of Force times Distance.

Since the dresser hasn't budged yet, the Distahce is zero. So no matter how great the Force may be, it's multiplied by zero, so the Work is zero.

5 0

4 years ago