Question
help with number 2
A 9.30-kg hanging object is connected by a light, inextensible cord over a light, frictionless pulley to a 5.00-kg block that is sliding on a flat table. Taking the coefficient of kinetic friction as 0.237, find the tension in the string. A 27.0-kg block is initially rest on a horizontal surface. A horizontal force of 77.0 N is required to set the block in motion, after which a horizontal force of 63.0 N is required to keep the block moving with the constant speed. Find the coefficient of static friction between the block and the surface. Find the coefficient of kinetic friction between the block and the surface. In the Bohr model of the hydrogen atom, an electron moves in a circular path around a proton. The speed of the electron is approximately 225 times10^6 m/s. Find the force acting an electron as it revolves in circular orbit of radius 5.39 times 10^-11 m Find the centripetal acceleration the electron
Explanation / Answer
2)
here,
m1 = 9.3 kg
m2= 5 kg
uk = 0.237
the accelration , a = (m1 * g - uk * m2 * g )/( m1 + m2)
a = ( 9.3 * 9.81 - 0.237 * 5 * 9.81)/( 9.3 + 5)
a = 5.57 m/s^2
the teniosn in the string , T = m2 * g - m2 * a
T = 9.3 * ( 9.81 - 5) N
T = 39.5 N
