Answer: She is incorrect to conclude that the reaction is endothermic.
As in the second trial, the temperature has increased by 20 °C , that means the heat has been released and energy is released in exothermic reactions.
Exothermic reactions: The reactions in which the energy of the products is less than the energy of the reactants, and the excess energy is released as heat.
Endothermic reactions: The reactions in which the energy of the products is more than the energy of the reactants, and the excess energy is absorbed as heat.
Answer:
6.71×10⁻⁷ m
Explanation:
Using thin film constructive interference formula as:
<u>2×n×t = m×λ</u>
Where,
n is the refractive index of the refracted surface
t is the thickness of the surface
λ is the wavelength
If m =1
Then,
2×n×t = λ
Given that refractive index pf the oil is 1.22
Thickness of the oil = 275 nm
Also, 1 nm = 10⁻⁹ m
Thickness = 275×10⁻⁹ m
So,
Wavelength is :
<u>λ= 2×n×t = 2× 1.22 × 275×10⁻⁹ m = 6.71×10⁻⁷ m</u>
Answer:
(a) - 165.032 m/s
(b) 238.37 m/s
Explanation:
initial horizontal velocity, ux = 172 m/s
height, h = 1390 m
g = 9.8 m/s^2
Let it strikes the ground after time t.
Use second equation of motion in vertical direction
-1390 = 0 - 0.5 x 9.8 x t^2
t = 16.84 second
(a) Let vy be the vertical component of velocity as it strikes the ground
Use first equation of motion in vertical direction
vy = uy - gt
vy = 0 - 9.8 x 16.84
vy = - 165.032 m/s
Thus, the vertical component of velocity as it strikes the ground is 165.032 m/s downward direction.
(b)
The horizontal component of velocity remains constant throughout the motion.
vx = 172 m/s
vy = - 165.032 m/s
The resultant velocity is v.
v = 238.37 m/s
Thus, teh velocity with which it hits the ground is 238.37 m/s.
Answer: A material called moderator is used to slow down the neutrons released during nuclear fission. The source's neutrons have a high speed and energy. The neutrons' speed is slowed by heavy water or graphite moderators.
Explanation:
it helps use less weight to pick up things and makes it way easier to work
