Let v = the running speed
After running at constant speed for 26 min, the distance traveled is
d = (v m/min)*(26 min) = 26v m
Because there are 1500 m to go, the distance traveled is
10000 - 1500 = 8500 m
The running speed is
v = (8500 m)/(26 min) = 326.9 m/min
In km/h, the speed is
v = (0.3269 km/min)*(60 min/h) = 19.6 km/h
Answer: The running speed is 19.6 km/h
Answer:
238.75⁰C .
Explanation:
coefficient of linear thermal expansion of aluminum and steel is 23 x 10⁻⁶ K⁻¹ and 12 x 10⁻⁶ K⁻¹ respectively .
Rise in temperature be Δ t .
Formula for linear expansion due to heat is as follows
l = l₀ ( 1 + α x Δt )
l is expanded length , l₀ is initial length , α is coefficient of linear expansion and Δt is increase in temperature .
For aluminum
l = 2.5 ( 1 + 23 x 10⁻⁶ Δt )
For steel
l = 2.506 ( 1 + 12 x 10⁻⁶ Δt )
Given ,
2.5 ( 1 + 23 x 10⁻⁶ Δt ) = 2.506 ( 1 + 12 x 10⁻⁶ Δt )
1 + 23 x 10⁻⁶ Δt = 1.0024 ( 1 + 12 x 10⁻⁶ Δt )
1 + 23 x 10⁻⁶ Δt = 1.0024 + 12.0288 x 10⁻⁶ Δt
10.9712 x 10⁻⁶ Δt = .0024
Δt = 218.75
Initial temperature = 20⁰C
final temperature = 218.75 + 20 = 238.75⁰C .
Answer:
0.196 m
Explanation:
Given in the question that,
time taken by the dolphin to go back to water = 0.2 sec
To solve the question we will use Newton's Law of motion
<h3>S = ut + 0.5(a)t²</h3>
here S is distance covered
u is initial speed
a = acceleration due to gravity
t = time taken
Plug value in the equation above
S = 0(0.2) + 0.5(-9.8)(0.2)²
S = 0.5(-9.8)(0.2)²
S = -0.196 m
Negative sign represent direction
(Assuming that dolphin have a vertical straight jump not a projectile motion)
Answer:
λ = 6.61 x 10⁻⁷ m = 661 nm
Explanation:
From the Young's Double Slit experiment, the the spacing between adjacent bright or dark fringes is given by the following formula:
Δx = λL/d
where,
Δx = fringe spacing = 2.86 mm = 2.86 x ⁻³ m
L = Distance between slits and screen = 2.12 m
d = slit separation = 0.49 mm = 0.49 x 10⁻³ m
λ = wavelength of light = ?
Therefore,
2.86 x 10⁻³ m = λ(2.12 m)/(0.49 x 10⁻³ m)
(2.86 x 10⁻³ m)(0.49 x 10⁻³ m)/(2.12 m) = λ
<u>λ = 6.61 x 10⁻⁷ m = 661 nm</u>
Answer:
The given statement is correct.
When the light becomes brighter then the electron emitted per second increases.
when light is incident on the metal it delivers energy in the form of small energy packets.
these small energy packets is known as photons.
More the intensity of light more the photon will be emitted.
Electron gain kinetic energy after absorbing energy from the photon.
