Tornado- Trees knocked down, debris everywhere, ground and dirt scattered.
Answer:
D
Explanation:
speed is constant in a certain medium.
phase is not directly related to the energy.
intensity and wavelength both determin amount of energy carried by the wave. however, in this question in first examples wavelength is pointed out. I guess D is the correct answer.
For B and D:
![energy = \sqrt{ \frac{2 \times i}{c \times \: epsilon } } \: \: \: \\ energy = \frac{hc}{lambda}](https://tex.z-dn.net/?f=energy%20%3D%20%20%5Csqrt%7B%20%5Cfrac%7B2%20%5Ctimes%20i%7D%7Bc%20%5Ctimes%20%5C%3A%20epsilon%20%7D%20%7D%20%5C%3A%20%20%5C%3A%20%20%5C%3A%20%20%20%5C%5C%20energy%20%3D%20%20%5Cfrac%7Bhc%7D%7Blambda%7D%20)
the first one is relation between intensity (i) and energy.
the second one is the relation between wavelength (lambda) and energy.
Use the equation:
Resultant force= mass of body×acceleration(F=ma)
450N is the resultant force acting on the box since there is no friction to oppose it.
To find mass of box,
450=m×15
m=450÷15=30kg
<span>21.5 ft/s^2
The formula for distance traveled under constant acceleration is
d = 0.5 AT^2
where
d = distance
A = acceleration
T = time
Solving for A, gives
d = 0.5 AT^2
2d = AT^2
(1) 2d/T^2 = A
The formula for velocity under constant acceleration is
V = AT
Solving for A, gives
V = AT
(2) V/T = A
Now setting equations (1) and (2) above equal to each other and solving for T:
V/T = 2d/T^2
TV = 2d
(3) T = 2d/V
Now substitute equation (3) into (2) above.
V/T = A
V/(2d/V) = A
V * V/2d = A
V^2/2d = A
Plug in values and calculate.
V^2/2d = A
(44 ft/s)^2/(2*45 ft) = A
(1936 ft^2/s^2)/(90 ft) = A
21.51111111 ft/s^2 = A
Rounding to 3 significant figures gives 21.5 ft/s^2</span>
Answer:
correct answer is (c) 15 J
Explanation:
given data
mass m1 = 2 kg
velocity V1 = 5 m/s
mass other = 3 kg
so mass m2 = 2+ 3 kg = 5 kg
solution
we will apply here conservation of momentum:
m1V1 = m2V2 ..........................1
put here value and we get velocity v2
(2.0) × (5.0) = (2.0 + 3.0) × V
solve it we get
10 = 5 × V
2
V2 = 2.0 m/s
so here kinetic energy will be
KE = ½ × m × v²
so
∆KE = ½ × m1 × (v1)² - ½ × m2 × (v2)
²
∆KE = 0.5 × 2 × 25 - 0.5 × 5 × 4
∆KE = 25 - 10
∆KE = 15 J