Answer:
b
c
e
h
Explanation:
Note that the swing direction was not giving in the question and direction could be sideways (in a turn) or in a track or both
The question show something in common ...acceleration
So let's look at the statements and pick the correct ones
a is false while b is correct as the train is accelerating
c is correct. The train is accelerating even thou the speed could not be ascertained
d is false and not feasible as the train is accelerating
e is true as the train maybe moving at a constant speed in a circle
f is false. This could be constant velocity in a circle. Same as g (false)
h is true. It's accelerating
Explanation:
- Newton's first law of motion:
"An object at rest (or in uniform motion) remains at rest (or in uniform motion) unless acted upon an unbalanced force
In this situation, we can apply Newton's first law to the keys of the keyboard that are not hit by the fingers of the man. In fact, as no force act on the keys, they remain at rest.
- Newton's second law of motion:
"The acceleration experienced by an object is proportional to the net force exerted on the object; mathematically:

where F is the net force, m is the mass of the object, and a its acceleration"
In this case, we can apply Newton's second law to the keys of the keyboard that are hit by the man: in fact, as they are hit, they experience a downward force, and therefore they experience a downward acceleration.
"Newton's third law of motion:
"When an object A exerts a force on an object B (action force), then object B exerts an equal and opposite force on object A (reaction force)"
Here We can apply Newton's third law to the pair of objects finger-key: in fact, as the finger apply a force on the key (action force), then the key exerts a force back on the finger (reaction force), equal and opposite.
Answer:
Cp= 0.44 J/g.C
This is heat capacity of metal.
Explanation:
From energy conservation
Heat lost by metal = Heat gain by water +Heat gain by calorimeter
Because here temperature of metal is high that is why it loose the heat.The temperature of water and calorimeter is low that is why they gain the heat.
final temperature is T= 30.5 C
We know that sensible heat transfer given as
Q= m Cp ΔT
m=Mass
Cp=Specific heat capacity
ΔT=Temperature difference
By putting the values
55 x Cp ( 99.5 - 30.5) = 40 x 4.184 ( 30.5- 21 ) + 10 x ( 30.5 - 21)
Cp ( 99 .5- 30.5) = 30.65
Cp= 0.44 J/g.C
This is heat capacity of metal.
Where is the Temperature bud?
Answer:
The value of new coulomb force is 1.43 N.
Explanation:
Given;
Coulomb's force in vacuum (air),
= 10 N
dielectric constant, K = 7
The Coulomb's force between two charges separated by a distance r in a vacuum is given as;

The Coulomb's force between two charges separated by a distance r in a medium with dielectric constant is given as

Take the ratio of the two forces;

Therefore, the value of new coulomb force is 1.43 N.