How much gravitational potential energy does the block have
when it gets to the top of the ramp ?
(weight) x (height) = (15 N) x (0.2 m) = 3 Joules .
If there were no friction, you would only need to do 3 Joules of work
to lift the block from the bottom to the top.
But the question says you actually have to do 4 Joules of work
to get the job done.
Friction stole one of your Joules along the way.
Choice-4 is not the correct one.
Choice-1 is the correct one.
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Notice that the mass of the block is NOT 15 kg , and you
don't have to worry about gravity to answer this question.
The formula for potential energy is (m)·(g)·(h) .
But (m·g) is just the WEIGHT, and the formula
is actually (weight)·(height).
The question GIVES us the weight of the block . . . 15 N .
So the potential energy at the top is just (15N)·(0.2m) = 3 Joules.
No, Greenhouse gases in the air, mainly carbon dioxide, methane and water vapor, trap radiation from the Sun and act like a thermal blanket around the planet. Without the greenhouse effect, the Earth would have an average temperature of -18 °C and be covered in ice. Life as we know it would not be able to survive.
Answer:
T = 0.00889 N*m
Explanation:
Given the initial speed
Vo = 9.0rev/s.
V = 65 rev/10s
V = 6.5 rev/s.
V = Vo + a*t
Solve to acceleration knowing the initial velocity and the velocity at 10 s
6.5 rev/s - 9 rev/s = a*10s
a = -0.25 rev/s^2.
Now the solve the time at stop time so V=0
V = Vo + a*t
0 = 9.0 - 0.25 rev/s *t,
t = 36 s The Stopping time.
36s - 10s = 26s
The torque can be find using the acceleration using the equation
T = I*a
I = 1/2*m*r^2
I = 1/2*0.725kg*(0.315m)^2= 0.0359kg*m^2
T = 0.0359kg*m^2*-0.25rev/s^2
T = 0.00889 N*m
Answer:
Explanation:
Force between two charges of q₁ and q₂ at distance d is given by the expression
F = k q₁ q₂ / d₂
Here force between charge q₁ = - 15 x 10⁻⁹ C and q₃ = 47 x 10⁻⁹ C when distance between them d = (1.66 - 1.24 ) = .42 mm
k = 1/ 4π x 8.85 x 10⁻¹²
putting the values in the expression
F = 1/ 4π x 8.85 x 10⁻¹² x - 15 x 10⁻⁹ x 47 x 10⁻⁹ /( .42 x 10⁻³)²
= 9 x 10⁹ x - 15 x 10⁻⁹ x 47 x 10⁻⁹ /( .42 x 10⁻³)²
= 35969.4 x 10⁻³ N .
force between charge q₂ = 34.5 x 10⁻⁹ C and q₃ = 47 x 10⁻⁹ C when distance between them d = ( 1.24 - 0 ) = 1.24 mm .
putting the values in the expression
F = 1/ 4π x 8.85 x 10⁻¹² x 34.5 x 10⁻⁹ x 47 x 10⁻⁹ /( .42 x 10⁻³)²
= 9 x 10⁹ x - 34.5 x 10⁻⁹ x 47 x 10⁻⁹ /( .42 x 10⁻³)²
= 82729.6 x 10⁻³ N
Both these forces will act in the same direction towards the left (away from the origin towards - ve x axis)
Total force = 118699 x 10⁻³
= 118.7 N.
Answer:
So option (b) will be correct option
Explanation:
We have given that there is a step up transformer in which number of turns in primary coil is 15
That is,
Primary voltage , and secondary voltage
We have to find the number of turns in the secondary \
We know that for the transformer
So option (b) will be correct option