Answer: The correct option is (c.).
Explanation:
Mass of the cart A= 1.5 kg
Velocity of Cart A = 1.4 m/s towards right
Mass of the cart B = 1.0 kg
Velocity of Cart B = 1.4 m/s towards left
Momentum (P)= Mass × Velocity

(Negative sign means velocity of the cart is in opposite direction of that of the cart A)
Total Momentum =
Hence, the correct option is (c.).
Answer: f=150cm in water and f=60cm in air.
Explanation: Focal length is a measurement of how strong light is converged or diverged by a system. To find the variable, it can be used the formula:
= (nglass - ni)(
-
).
nglass is the index of refraction of the glass;
ni is the index of refraction of the medium you want, water in this case;
R1 is the curvature through which light enters the lens;
R2 is the curvature of the surface which it exits the lens;
Substituting and calculating for water (nwater = 1.3):
= (1.5 - 1.3)(
-
)
= 0.2(
)
f =
= 150
For air (nair = 1):
= (1.5 - 1)(
-
)
f =
= 60
In water, the focal length of the lens is f = 150cm.
In air, f = 60cm.
Answer:
Speed= 6cm/s and velocity= 6cm/s in the negative direction
Explanation:
the change in position is from 45cm to 27 cm (moving towards the negative x direction)

And the change in time:

Now we must define the difference between speed and velocity:
Speed is a scalar quantity, which means that it is a number. Velocity is also a number but you must also indicate the direction of the movement.
Thus, the speed is:

An the velocity is:
6cm/s in the negative direction
Answer:
Amoeba (plural = amoebae) is a well known genus of unicellular organism, a protist. One of its most common species, the Amoeba Proteus, is about 0.2 to 0.3 mm large. The amoeba was first discovered by August Von Rosenhof in 1757.[1] It is a genus of protozoa that moves with false feet, called pseudopodia.