Answer:
a = 8 m/s^2, Ffriction = 10 N, μk = 0.205
Explanation:
a. Force = Mass*Acceleration,
(since you didn't add the units..."5 block"....for the mass, I will assume it to be in kg, per SI units)
40 N = 5 kg*acceleration,
a = 40/5 = 8 m/s^2
b. As you know newtons second law (F=m*a) is actually in the form Fnet = m*a. Which means that if the friction force comes into play, it would be Fapplied - Ffriction = m*a.
Fapplied - Ffriction = m*a,
40 - Ffriction = 5*6,
40 - Ffriction = 30,
Ffriction = 40 - 30 = 10 N
c. The coefficient of kinetic friction is calculated by the formula "Ffriction = μk*Fnormal".
10 = μk*Fnormal (Fnormal = m*g = 5*9.8)
10 = μk*49,
μk=10/49 ≈ 0.205
At certain altitude, the temperature of air decrease, The air becomes saturated and water vapour molecules starts condensing.
As the altitude of air increase, the atmospheric pressure decrease due to which the temperature of the air decrease. The water molecules in the atmosphere start condensing, which saturate the air (that is air can no hold water molecules), due to which the water vapour molecules starts condensing and falls on the earth in the form of rain.
Since you already gave us the weight of the 2.5-kg box,
we don't even need to know what the distance is, just
as long as it doesn't change.
Look at the formula for the gravitational force:
F = G m₁ m₂ / R² .
If 'G', 'm₁' (mass of the Earth), and 'R' (distance from the Earth's center)
don't change, then the Force is proportional to m₂ ... mass of the box,
and you can write a simple proportion:
(6.1 N) / (2.5 kg) = (F) / (1 kg)
Cross-multiply: (6.1 N) (1 kg) = (F) (2.5 kg)
Divide each side by (2.5 kg): F = (6.1N) x (1 kg) / (2.5 kg) = 2.44 N .
Answer: C) 200 N
Explanation:
The force
is defined as:

Where:
is the mass of the object
is the acceleration
Then:

Finally:

Hence, the correct option is C.