A stone is thrown vertically upward with a initial speed of 19.5m/s. What is the maximum height which it covers?
v = at t = 2 sec.it takes 2 seconds for the stone to slow down amd reach max height.the stone will then fall for two seconds starting from zero speed and traveling the same distanced= 1/2at^2d = .5*9.8*2^2d = 9.8*2 = 19.6m19.6m is the answer
What is an expression for the magnetic dipole moment of a revolving electron?
This derivation is according to NCERT.
What is a unit vector and why do we use it for?
A unit vector simply denotes the direction. If we have a vector 4i + 3j. I will use a 2D vector because it is easier to understand.The magnitude of this vector is 5 units.The unit vector will be 0.8i + 0.6j.When you plot this unit vector on a graph paper. Along x axis, go 0.8 units. From this point, go up 0.6 units parallel to the y axis. The resultant will be 1 (the hypotenuse length).If the value 5 is multiplies with this unit vector, it simply means that you produce the same effect of the vector 4i + 3j. with the vector 5 times 0.8i + 0.6j.
A light string passing over a smooth light pulley connects two blocks masses M and m (M>m) vertically. If the acceleration of the system is g/8,then the ratio of the masses M to m is?
M : m :: 9 : 7Complete solution in the picture below :
For a particle moving in a straight line, the displacement of the particle at time [math]t[/math] , is given by [math]s = t^3-6t^2+3t+7[/math]. What is the velocity of the particle when its acceleration is zero?
Given :s=t³-6t²+3t+7Let the velocity of the particles be V.Velocity(V) = ds/dt∴ V= ds/dt = 3t²-12t+3Hence,the acceleration of the particles will be :a = dv/dta = 6t-12But, a = 0It follows that :6t-12=0∴ 6t = 12∴ t = 2sTherefore,V = 3(2)² - 12(2) + 3,when t= 2sV = 12 - 24 + 3V = -9m/sV = 9m/s
What would gravity be like in the center of the earth?
It's not physically possible to make a hollow space at the center of the Earth - there is no material that is strong enough to withstand the pressure of the overlying metal and rock without being a continuous medium. Any void space that magically existed would promptly and violently collapse inwards.In answer to your next question: In the middle of the Earth, gravity is very nearly zero. This is because the Earth is nearly spherical, and the gravity inside a spherical shell is zero (this is described by something called the shell theorem ). However, the pressure at the center of the Earth is extremely high, because of all of the weight of the entire planet pushing inwards onto it.If you had a hollow space station filled with air, you would experience a slight gravitational force pulling you towards the station's center - due to the mass of the air itself. This isn't significant on something the size of the ISS; where internal air currents are much more important.