B-friction acts in direction opposite to objects motion
Answer: The average velocity is 150 km/h
Explanation: 70+80=150
Answer:
F = force
f = friction
u = coefficient of friction
R = normal reaction force
a = Acceleration
m = mass of block
g = gravity
f = uR
F = Ma
Say the block is moving to the right.
The 146N force thus acts to the right, and the friction force to the left, since it resists movement.
The 146N force acts to the right, but the horizontal component of it is 146 cos 50 = 93.84: So this is the force to the right.
Since F = uR and we're trying to find u, we need both F and R. R is easy to get since it is just m x g. This is in fact already given as the weight 350N. So R = 350.
The block is moving at a constant speed, so the force to the right must = the force to the left.
F = ma, so 93.84 - f = (350/g) x 0
This means f must be 93.84 also.
so we have f = uR,
93.84 = u x 350
so u = 0.268 or
0.27 to 2dp.
Hope you understand this.
Explanation:
<span>Once the presence of certain substances in a sample is known, the study of their absolute or relative abundance can help in determining specific properties. Gravimetric analysis yields more accurate data about the composition of a sample than volumetric analysis but also takes more time to perform in the laboratory.</span>
If the airplane covered 790 kilometers along the ground every hour,
and if it could keep that up, and if there was no wind, and if the
airplane pointed its nose directly toward its destination and never
zigged or zagged even the slightest bit, then it would cover
790 kilometers of the distance during the first hour, another
790 kilometers of the distance during the second hour, another
790 kilometers of the distance during the third hour, 790 more
kilometers of the distance during the fourth hour, and so forth
and so on until it had arrived at its destination.
The minimum time it would need for the total trip would be
(4,700 kilometers) / (790 kilometers per hour) =
5.9494... hours (rounded)
5hours 56m 57.7seconds (rounded) .
(790 kilometers) x (1 mile / 1.609344 kilometers) = 490.88 miles (rounded)
