Answer:
An electron has a negative electric charge.
Answer:

where E = electric field intensity
Explanation:
As we know that plastic ball is suspended by a string which makes 30 degree angle with the vertical
So here force due to electrostatic force on the charged ball is in horizontal direction along the direction of electric field
while weight of the ball is vertically downwards
so here we have


since string makes 30 degree angle with the vertical so we will have





where E = electric field intensity
Answer:

Explanation:
given,
length of the ship = 120 m
length of model of the ship = 4 m
Speed at which the ship travels = 70 km/h
speed of model = ?
by using froude's law

for dynamic similarities




hence, the velocity of model will be 12.78 km/h
Answer:(a)360N,(b)171N,(c)2.702m
Explanation:
(a)Maximum Friction Force =
=360 N


(b)Moment about Ground Point




(c)

Here maximum friction force can be 360 N
Therefore 
Where x is the maximum distance moved by man along the ladder

740x=2000
x=2.702m
Answer:
#See solution for details.
Explanation:
-Chemical energy in the battery is converted into Electrical Energy which powers up the phone.
-The electrical energy is then converted to Light Energy when the phone is powered up, this is seen through the lightening up of the phone screen.
-During phone calls, the electrical energy is further converted to Sound Energy to allow for transmission of audio signals.
- As we continue to use the phone, the electrical energy is converted into heat energy which we feel due to an overheating battery.
-The cycle then repeats itself again whenever a phone is charged.