Answer:
(a) 4.21 m/s
(b) 24.9 N
Explanation:
(a) Draw a free body diagram of the object when it is at the bottom of the circle. There are two forces on the object: tension force T pulling up and weight force mg pulling down.
Sum the forces in the radial (+y) direction:
∑F = ma
T − mg = m v² / r
v = √(r (T − mg) / m)
v = √(0.676 m (54.7 N − 1.52 kg × 9.8 m/s²) / 1.52 kg)
v = 4.21 m/s
(b) Draw a free body diagram of the object when it is at the top of the circle. There are two forces on the object: tension force T pulling down and weight force mg pulling down.
Sum the forces in the radial (-y) direction:
∑F = ma
T + mg = m v² / r
T = m v² / r − mg
T = (1.52 kg) (4.21 m/s)² / (0.676 m) − (1.52 kg) (9.8 m/s²)
T = 24.9 N
<span>Amorphous silica has a density of about 2.2 g/cm3, whereas the density of crystalline quartz is 2.65 g/cm3
</span><span>The difference in densities is
The atoms in amorphous silica do not pack as efficiently in three dimensions as compared to the atoms in quartz.
hope it helps</span>
The mesosphere is the coldest layer of the atmosphere. It is located above the stratosphere.
In scientific notation, if the exponent of 10 is positive, the number is very very large. In the metric system, very large numbers are expressed in megameters (Mm) or gigameters (Gm). Gigameters is equal to 10⁹ meters. So, in SI prefix, that would be equal to 150 Gm. In kilometers, that would be equal to:
1.5×10¹¹ m * (1 km/1000 m) = 1.5×10⁸ km
