Answer:
a) Earth
b) Mercury
c) Neptune
Explanation:
All the planets move around the sun in eastward direction, but few planet have retrograde rotation i.e in westward direction. Retrograde motion is just an apparent change in the movement of planet which means it only seems as if the planet are rotating in opposite direction. Retrograde movement of planet like Saturn, Jupiter and mars is not real. Hence, if a person lives on Saturn, then following planets will exhibit retrograde motion
a) Earth
b) Mercury
c) Neptune
Answer:
23.1 N/C
Explanation:
OP = 3 m , OQ = 4 m
q = - 8 nC, Q = 75 nC
Electric field at P due to the charge Q is
Electric field at P due to the charge q is
According to the diagram, tanθ = 3/4
Resolve the components of E1 along x axis and along y axis.
So, Electric field along X axis, Ex = - E1 Cos θ
Ex = - 27 x 4 / 5 = - 21.6 N/C
Electric field along y axis, Ey = E1 Sinθ - E2
Ey = 27 x 3 /5 - 8 = 8.2 N/C
The resultant electric field at P is given by
Answer:
B. 4 m/s
Explanation:
v=d/t
Running for 300 m at 3 m/s takes 100 seconds and running at 300 m at 6 m/s takes 50 seconds. 100 s + 50 s = 150 s (total time). Total distance is 600 m, so 600 m/ 150 s = 4 m/s.
Answer:
his is an example of the transformation of gravitational potential energy into kinetic energy
Explanation:
The game of juggling bowling is a clear example of the conservation of mechanical energy,
when the bolus is in the upper part of the path mechanical energy is potential energy; As this energy descends, it becomes kinetic energy where the lowest part of the trajectory, just before touching the hand, is totally kinetic.
At the moment of touching the hand, a relationship is applied that reverses the value of the speed, that is, now it is ascending and the cycle repeats.
Therefore this is an example of the transformation of gravitational potential energy into kinetic energy
Answer:
Tension in the string at this position: 3.1 N.
Explanation:
Convert the radius of the circle to meters:
.
What's the net force on the object?
The object is in a circular motion. As a result,
,
where
is the net force on the object,
is the mass of the object, 
is the velocity of the object, and
is the radius of the circular motion.
For this object,
.
The output unit of net force should be standard if the unit for mass, velocity, and radius are all standard. The net force shall always point towards the center. In this case the net force points downwards.
What are the forces on this object?
There are two forces on the object at this moment:
- Weight,
, which points downwards. 
. - Tension,
, which also points downwards. The size of the tension force needs to be found.
What's the size of the tension force?
Gravity and tension points in the same direction. The size of their resultant force is the sum of the two forces. In other words,
.
.
All three values in this question are given with two sig. fig. Round the value of to the same number of significant figures.
