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:
Velocity=1.1m/s
Amplitude=0.35m
Explanation:
Given:
time 't' = 2.9s
wavelength 'λ'= 5.5m
distance 'd'=0.7m
The time period 't' is the time b/w two successive waves. Therefore, the time it takes from the boat to travel from its highest point to its lowest is a half period.
So, T = 2 x 2.9 => 5.8 s
As we know that frequency is the reciprocal of time period, we have
f= 1/T = 1/5.8 =>0.2 Hz
In order to find how fast are the waves traveling, the velocity is given by
Velocity = f λ
V= 0.2 x 5.5 =>1.1m/s
The distance between the boat's highest point to its lowest point is double the amplitude.
Therefore , we can write
Amplitude 'A'= d/2 =>0.7/2 =>0.35m
Strength of induced current increased when strength of magnetic field increases. It will also increase when the number of turns are increased or if the speed of conductor increases
Answer:
The value is 
Explanation:
From the question we are told that
The distance of friends house from your point is 
The distance of your friends street from your street is 
The diagram illustrating this question is shown on the first uploaded image
From the diagram we can apply by Pythagoras theorem as follows
=> 
=> 
=>
Answer:
5 weeks and 5 days is required to empty the lake
Explanation:
Officials begin the remove water from a full man made lake
The lake can be emptied in 4 weeks
= -1/4
A river can fill the lake up in 15 weeks
= 1/15
Let t represent the number of weeks that is required to empty the lake
= -1/t
Therefore the number of weeks it takes to empty the lake can be calculated as follows
-1/t= -1/4 + 1/15
-1/t= -11/60
Cross multiply
-11×t= -1×60
-11t= -60
t = 60/11
t= 5 5/11
Hence it takes 5 weeks and 5 days to empty the lake
