A700-gram grinding wheel 28.5 cm in diameter is in the shape of a uniform solid disk. (we can ignore the small hole at the center.) when it is in use, it turns at a constant 210 rpm about an axle perpendicular to its face through its center. when the power switch is turned off, you observe that the wheel stops in 41.0 s with constant angular acceleration due to friction at the axle. part a what torque does friction exert while this wheel is slowing down?

0.01524 Nm

Explanation:

= Final angular velocity = 0

= Initial angular velocity = 210 rpm

= Angular acceleration

= Angle of rotation

t = Time taken = 41 seconds

Converting rpm to rad/s

m = Mass of wheel = 700 g

r = Radius of wheel = 28.5 cm

Equation of rotational motion

Moment of inertia of a disc is given by

Torque is given by

The torque the friction exerts while slowing down is 0.01524 Nm

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.