Could you please answer these questions 1- 2- 3 - 4- thank you An electric motor

Question

Could you please answer these questions

1-

2-

3-

4-

thank you

An electric motor rotating a workshop grinding wheel at 1.18 Times 102 rev/min is switched off. Assume the wheel has a constant negative angular acceleration of magnitude 1.90 rad/s2, How long does it take the grinding wheel to stop? S Through how many radians has the wheel turned during the time interval found in part (a)? rad A dentist's drill starts from rest. After 3.30 s of constant angular acceleration, it turns at a rate of 2.51 Times 104 rev/min. Find the drill's angular acceleration. rad/s2 (along the axis of rotation) Determine the angle through which the drill rotates during this period, rad Two vectors are given by A = -3i + 8j - 3k and B = 8i - 12j + Ilk. Evaluate the following quantities, cos-1 give(s) the angle between the vectors? A particle of mass 0.500 kg is attached to the 100-cm mark of a meterstick of mass 0.175 kg. The meterstick rotates on the surface of a frictionless, horizontal table with an angular speed of 2.00 Calculate the angular momentum of the system when the stick is pivoted about an axis perpendicular to the table through the 50.0-cm mark. Calculate the angular momentum of the system when the stick is pivoted about an axis perpendicular to the table through the 0-cm mark.

Explanation / Answer

1. a) w = w0 + alpha t

0 = (118*2*pi/60) - 1.9*t
t=6.5 s

b) theta = w0 t + 1/2 alpha t^2 = (118*2*pi/60)*6.5 - 0.5*1.9*6.5^2= 40.18

2) a) w = w0 + alpha t

2.51E4*2*pi/60 = alpha*3.3
alpha = 796.5

b) theta = w0 t + 1/2 alpha t^2 = 0.5*796.5*3.3^2= 4337

3) |A| = sqrt( 3^2 + 8^2 + 3^2)= 9.055

|B| = sqrt(8^2 + 12^2+11^2)= 18.138
A*B = -3*8 +8*-12 -3*11= -153

a) arcos( -153/(9.055*-153))= 83.66

b) arcsin = 6.34

c) arcos does so a

4) a) L = I w
through middle I = 1/12 m L^2 + m r^2
L = (1/12*0.175*1^2 + 0.5*.5^2)*2= 0.279

b) I about end = 1/3 mL^2 + mr^2
L = (1/3*0.175*1^2 + 0.5*1^2)*2=1.117

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.