A force is a push or a pull that acts upon an object as a results of its interaction with another object. ... These two forces are called action and reaction forces and are the subject of Newton's third law of motion. Formally stated, Newton's third law is: For every action, there is an equal and opposite reaction.
A Dodge Stealth is driving at 70 mph on a highway. It passes a BMW going the same direction. The BMW is moving 7 mph backward relative the Dodge. 63 mph is the velocity of the BMW
Answer: Option A
<u>Explanation:</u>
Given is the speed of the dodge stealth as 70 mph passing by the BMW moving with 7 mph relative to Dodge. Thereby, to calculate the velocity of BMW, relative velocity concept has to be employed.
As we know that the relative velocity tells us about relative velocity of mobile reference system as the difference or sum of the initial reference system.
Therefore,
velocity of the BMW = 
Velocity of the dodge = 
Velocity of the BMW with respect to dodge = 
As per the formula,


Answer:
An electromagnet is a magnet that runs on electricity. Unlike a permanent magnet, the strength of an electromagnet can easily be changed by changing the amount of electric current that flows through it. The poles of an electromagnet can even be reversed by reversing the flow of electricity.
Answer:
Explanation:
Using Boyles law
Boyle's law states that, the volume of a given gas is inversely proportional to it's pressure, provided that temperature is constant
V ∝ 1 / P
V = k / P
VP = k
Then,
V_1 • P_1 = V_2 • P_2
So, if we want an increase in pressure that will decrease volume of mercury by 0.001%
Then, let initial volume be V_1 = V
New volume is V_2 = 0.001% of V
V_2 = 0.00001•V
Let initial pressure be P_1 = P
So,
Using the equation above
V_1•P_1 = V_2•P_2
V × P = 0.00001•V × P_2
Make P_2 subject of formula by dividing be 0.00001•V
P_2 = V × P / 0.00001 × V
Then,
P_2 = 100000 P
So, the new pressure has to be 10^5 times of the old pressure
Now, using bulk modulus
Bulk modulus of mercury=2.8x10¹⁰N/m²
bulk modulus = P/(-∆V/V)
-∆V = 0.001% of V
-∆V = 0.00001•V
-∆V = 10^-5•V
-∆V/V = 10^-5
Them,
Bulk modulus = P / (-∆V/V)
2.8 × 10^10 = P / 10^-5
P = 2.8 × 10^10 × 10^-5
P = 2.8 × 10^5 N/m²
Answer:0.00125 watts
Explanation:
resistance=50 ohms
Current=5 milliamps
Current=5/1000 milliamps
Current =0.005 amps
power=(current)^2 x (resistance)
Power=(0.005)^2 x 50
Power=0.005 x 0.005 x 50
Power=0.00125 watts