The van's AVERAGE speed on the way up the hill is
(1/2) (20 + 12) = (1/2) (32) = 16 m/s .
At an average speed of 16 m/s, it travels
(16 m/s) x (8 s) = 128 meters in 8 seconds.
Answer:
The diameter of the lead cylinder is 1.35 cm.
Explanation:
Given that,
Density of silver = 10.5 g/cm³
Density of lead = 11.3 g/cm³
Diameter = 1.4 cm
As mass of both is equal.
Let diameter of lead ![d_{l}](https://tex.z-dn.net/?f=d_%7Bl%7D)
We need to calculate the the diameter of the lead cylinder
Using balance equation of density
![V\times \rho_{s}=V\times \rho_{l}](https://tex.z-dn.net/?f=V%5Ctimes%20%5Crho_%7Bs%7D%3DV%5Ctimes%20%5Crho_%7Bl%7D)
![\dfrac{\pi\times d_{s}^2\times h}{4}\times\rho_{s}=\dfrac{\pi\times d_{l}^2\times h}{4}\times\rho_{s}](https://tex.z-dn.net/?f=%5Cdfrac%7B%5Cpi%5Ctimes%20d_%7Bs%7D%5E2%5Ctimes%20h%7D%7B4%7D%5Ctimes%5Crho_%7Bs%7D%3D%5Cdfrac%7B%5Cpi%5Ctimes%20d_%7Bl%7D%5E2%5Ctimes%20h%7D%7B4%7D%5Ctimes%5Crho_%7Bs%7D)
![d_{l}^2=\dfrac{d_{s}^{2}\times\rho_{s}}{\rho_{l}}](https://tex.z-dn.net/?f=d_%7Bl%7D%5E2%3D%5Cdfrac%7Bd_%7Bs%7D%5E%7B2%7D%5Ctimes%5Crho_%7Bs%7D%7D%7B%5Crho_%7Bl%7D%7D)
put the value into the formula
![d_{l}^2=\dfrac{(1.4\times10^{-2})^2\times10.5}{11.3}](https://tex.z-dn.net/?f=d_%7Bl%7D%5E2%3D%5Cdfrac%7B%281.4%5Ctimes10%5E%7B-2%7D%29%5E2%5Ctimes10.5%7D%7B11.3%7D)
![d_{l}=\sqrt{0.00018212}](https://tex.z-dn.net/?f=d_%7Bl%7D%3D%5Csqrt%7B0.00018212%7D)
![d_{l}=0.0135\ m](https://tex.z-dn.net/?f=d_%7Bl%7D%3D0.0135%5C%20m)
![d_{l}=1.35\ cm](https://tex.z-dn.net/?f=d_%7Bl%7D%3D1.35%5C%20cm)
Hence, The diameter of the lead cylinder is 1.35 cm.
Answer:
19.5 m/s
87.8 m
Explanation:
The acceleration of block one is:
∑F = ma
-m₁gμ = m₁a
a = -gμ
a = -(9.8 m/s²) (0.22)
a = -2.16 m/s²
The velocity of block one just before the collision is:
v² = v₀² + 2aΔx
v² = (8.25 m/s)² + 2 (-2.16 m/s²) (2.3 m)
v = 7.63 m/s
Momentum is conserved, so the velocity of block two just after the collision is:
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂
m₁u₁ = m₂v₂
(18.5 kg) (7.63 m/s) = (7.25 kg) v
v = 19.5 m/s
The acceleration of block two is also -2.16 m/s², so the distance is:
v² = v₀² + 2aΔx
(0 m/s)² = (19.5 m/s)² + 2 (-2.16 m/s²) Δx
Δx = 87.8 m
Here are the stages of a silkworm lifecycle
1. The female lays the eggs
2. A tiny black Caterpillar hatches out of the egg
3. The Caterpillar eats mulberry leaves and grows bigger, it goes through 4 molts.
<u>4. The Caterpillar spins a cocoon of silk threads</u>
5. inside the cocoon the Caterpillar changes into a pupa
6. The pupa changes into a moth, then the moth comes out
7. The adult moths mate with each other
hope this helps!
Answer:
False.
Explanation:
The forces acting on the rocket would be the engine pushing it forward, but it would also be the force of gravity and air friction acting in the reverse direction of the force of the engine. And so some energy in the form of heat, vibration, etc. would be lost to these forces, and the maximum amount of work would not be converted into kinetic energy.
So it's wrong with the statement. The work done by the engine-generated power would be higher than the Kinetic energy, as some of the energy is lost to non-conservative forces (gravity, air resistance, etc.).