Answer:
b)
Explanation:
By convention, the electric field lines (which are tangent to the direction of the electric field at a given point) always begin at positive charges, and finish at negative charges.
This is a consequence of the convention that states that the electric field has the direction of the trajectory of a positive test charge when released from rest in an electric field.
(As the positive charge would move away from positive charges and would be attracted by negative ones).
So, the combination of answers that is true is b) (positive, negative, positive).
Answer:
Explanation:
Velocity can be found using the following formula:
where p is the momentum and m is the mass.
The woman has a mass of 55 kilograms and a momentum of 200 kilogram meters per second.
Substitute the values into the formula.
Divide. Note that the kilograms, or kg, will cancel each other out.
The woman's velocity is 3.63636364 meters per second.
Answer:
The inlet velocity is 21.9 m/s.
The mass flow rate at reach exit is 1.7 kg/s.
Explanation:
Given that,
Mass flow rate = 2 kg/s
Diameter of inlet pipe = 5.2 cm
Fifteen percent of the flow leaves through location (2) and the remainder leaves at (3)
The mass flow rate is
We need to calculate the mass flow rate at reach exit
Using formula of mass
We need to calculate the inlet velocity
Using formula of velocity
Put the value into the formula
Hence, The inlet velocity is 21.9 m/s.
The mass flow rate at reach exit is 1.7 kg/s.
Answer:
beam of light converges to a point A. A lens is placed in the path of the convergent beam 12 cm from P.
To find the point at which the beam converge if the lens is (a) a convex lens of focal length 20 cm, (b) a concave lens of focal length 16 cm
Solution:
As per the given criteria,
the the object is virtual and the image is real (as the lens is placed in the path of the convergent beam)
(a) lens is a convex lens with
focal length, f=20cm
object distance, u=12cm
applying the lens formula, we get
f
1
=
v
1
−
u
1
⟹
v
1
=
f
1
+
u
1
⟹
v
1
=
20
1
+
12
1
⟹
v
1
=
60
3+5
⟹v=7.5cm
Hence the image formed is real, at 7.5cm from the lens on its right side.
(b) lens is a concave lens with
focal length, f=−16cm
object distance, 12cm
applying the lens formula, we get
f
1
=
v
1
−
u
1
⟹
v
1
=
f
1
+
u
1
⟹
v
1
=
−16
1
+
12
1
⟹
v
1
=
48
−3+4
⟹v=48m
Hence the image formed is real, at 48 cm from the lens on the right side.
