Answer:
Nora's boat is moving towards Sam at 5 km/hr
Explanation:
The question says that Nora is few meters behind Nancy and is still with respect to her that means the relative velocity between Nora and Nancy is zero
Vrel = 5 - Vnora= 0 ⇒ Vnora = 5km/hr
Pictorially we can represent the given condition as:
Nora-------few meters------Nancy ----------------- Sam
5km/hr 5km/hr →
Hence, Nora's boat is moving towards Sam at 5km/hr.
The magnitude of the force on the charge by the influence of the magnetic field will be 6.6*10^-3 N
<h3>What is magnetic force?</h3>
Magnetic force, attraction or repulsion that arises between electrically charged particles because of their motion.The magnitude of the magnetic force acting on the charge is given by:

where
The magnitude of the charge 
The velocity of the charge 
The magnitude of the magnetic field 
The angle between the directions of v and B 
By substituting the values we will get:


Hence the magnitude of the force on the charge by the influence of the magnetic field will be 6.6*10^-3 N
To know more about Magnetic force follow
brainly.com/question/14411049
The North Magnetic Pole is the point on the surface of Earth's Northern Hemisphere at which the planet's magnetic field points vertically downwards (in other words, if a magnetic compass needle is allowed to rotate about a horizontal axis, it will point straight down). There is only one location where this occurs, near (but distinct from) the Geographic North Pole and the Geomagnetic North Pole.
The frequency, f, of a wave is the number of waves passing a point in a certain time. We normally use a time of one second, so this gives frequency the unit hertz (Hz), since one hertz is equal to one wave per second.
Answer:
Speed of the car 1 =
Speed of the car 2 =
Explanation:
Given:
Mass of the car 1 , M₁ = Twice the mass of car 2(M₂)
mathematically,
M₁ = 2M₂
Kinetic Energy of the car 1 = Half the kinetic energy of the car 2
KE₁ = 0.5 KE₂
Now, the kinetic energy for a body is given as

where,
m = mass of the body
v = velocity of the body
thus,

or

or

or

or

or
.................(1)
also,

or

or

or

or

or

or

or

or

and, from equation (1)

Hence,
Speed of car 1 =
Speed of car 2 =