Answer:
The magnitude of electric field is 22.58 N/C
Solution:
Given:
Force exerted in upward direction, 
Charge, Q = 
Now, we know by Coulomb's law,

Also,
Electric field, 
Thus from these two relations, we can deduce:
F = QE
Therefore, in the question:



Here, the negative side is indicative of the Electric field acting in the opposite direction, i.e., downward direction.
The magnitude of the electric field is:

Answer:
D). 
Explanation:
As we know that temperature scale is linear so we will have

now we have

so the relation between two scales is given as

now we know that in kelvin scale the absolute temperature is 600 K
so now we have

so correct answer is
D). 
Answer: A voltmeter must have a high resistance where as an ammeter must have a low resistance.
Explanation:
A voltmeter is a device which is connected in parallel to the component across which voltage needs to be measured. In a parallel circuit voltage drop is same at the nodes. The parallel connection must not offer easier path for current to divert from the main circuit and travel. Thus, a voltmeter must have high resistance.
On the other hand, an ammeter which is used to measure current in the circuit must have low resistance as it is connected in series. It should not offer resistance as it would reduce the actual current and measurement would be inaccurate.
This is a concept of momentum. In equation, momentum is the product of force and distance. When a ball is thrown, its force is constant all throughout unless disturbed by an external force. Therefore, force is the constant of proportionality that relates momentum with distance. When you block a ball from a given distance, you would feel the great force on your hand. In order to reduce the force, you have to follow the direction of the force in order to minimize the impact. By doing this, you gradually decrease the momentum of the ball.
Answer:
She must stop the car before interception, distance traveled 12.66 m
Explanation:
We will take all units to the SI system
Vo = 48Km / h (1000m / 1Km) (1h / 3600s) = 13.33 m / s
V2 = 70 Km / h = 19.44 m / s
We calculate the distance traveled before stopping
X = Vo t + ½ to t²
Time is what it takes traffic light to turn red is t = 2.0 s
X = 13.33 2 + 1.2 (-7) 2²
X = 12.66 m
It stops car before reaching the traffic light turning to red
Let's analyze what happens if you accelerate, let's calculate the acceleration of the vehicle
V2 = Vo + a t2
a = (V2-Vo) / t2
a = (19.44-13.33) /6.6
a = 0.926 m / s2
This is the acceleration to try to pass the interception, now let's calculate the distance it travels in the time the traffic light changes from yellow to red (t = 2.0 s)
X = Vo t + ½ to t²
X = 13.33 2 + ½ 0.926 2²
X = 28.58 m
Since the vehicle was 30 m away, the interception does not happen