No it is not, most bacteria is very helpful, it helps the body function and fight off diseases when the body is sick. Sometimes the good bacteria can't fight off the bad bacteria and will cause you to have to buy antibiotics. The antibiotics give the body a huge advantage at fighting off the disease and the body goes back to normal.

7 0

3 years ago

Calculate the friction of the person on ski. We use the situation from example 5.1 "Skiing Exercise" from the text book, but we

nalin [4]

Answer: Friction (Fk) = 46.2N.

Explanation: In the attachment, there is the drawing of the forces acting on the skiing person. As the person is in movement, the formula to calculate the friction is Fk = μk.N, where μk is the coefficient of kinetic friction and N is normal force. Normal force is the force necessary to keep a person "above" the ground. To find the normal force as suggested, we use the representation of the forces in the attachment. With it, it's shown that to calculate N:

cos 15° = $\frac{N}{Fg}$

N = Fg·cos 15°

N = 608·(-0.76)

N = - 461.9N

Now, with N and knowing the coefficient, which can be found in Physics Text Books and it is 0.1, we have:

Fk = 0.1·(-461.9)

Fk = - 46.2N

The friction is negative because it is pointing to the opposite side of the reference.

5 0

3 years ago