Answer:
The minimum force the climber must exert is about 439N.
Explanation:
We use the relationship between friction and normal force to answer this question:
We are given the static coefficients of friction but need to determine the friction force. To do that we consider the totality of forces acting on this hapless gentleman stuck in a chimney. There is the gravity acting downward (+), then there are two friction forces acting upward (-), namely through his shoes and his back. The horizontal force exerted by the climber on both walls of the chimney is the same and is met with equally opposing normal force. Since the climber is not falling the net force in the vertical direction is zero:
The normal force in this equilibrium is about 439N and because we are told that the static friction forces are both at their maximum, this value is at the same time the <em>minimum</em> force needed for the climber to avoid starting slipping down the chimney.
Answer:
Explanation:
We know that , for an object to remain in circular motion , a force towards centre is required which is called centripetal force. In the circular motion of
satellites around planet , this force is provided by the gravitational attraction between satellite and planet.
If M be the mass of planet and m be the mass of satellite, G be gravitational constant and R be the distance between planet and satellite or R be the radius of orbit
Gravitational force = G Mm / R²
If v be the velocity with which satellite is orbiting
centripetal force
= m v² /R
Centripetal force = gravitational attraction
m v² /R = G Mm / R²
v = 
Time period = time the satellite takes to make one rotation
= distance / orbital velocity
= 2πR/ v
= 
T = 
The amount of heat will be equal to Lm.
Where L is the latent heat of fusion and m is mass of the ice.
Latent heat of ice = 80cal/g.
So the amount of heat required here will be 35× 80cal
= 2,800 cal.
Measuring spoons are used when measuring less than 1/4 cup
Answer:
This relationship is explained by Ohm's law
Explanation:
Ohm's law states that the current flowing through a circuit or a resistor is directly proportional to the voltage across the resistor and inversely proportional to the resistance. Where current is i, voltage is v and resistance is r, Ohm's law can be represented mathematically as
V= IR
