(b) with a constant acceleration w (and the zero initial velocity),
while the disc rotates counterclockwise with a constant angular velocity (0.
1.52. A point A is located on the rim of a wheel of radius R
0.50 m which rolls without slipping along a horizontal surface
with velocity v = 1.00 m/s. Find:
(a) the modulus and the direction of the acceleration vector of the
point A;
(b) the total distance s traversed by the point A between the two
successive moments at which it touches the surface.
1.53. A ball of radius R = 10.0 cm rolls without slipping down
an inclined plane so that its centre moves with constant acceleration
Fig. 1.6.
Fig. 1.7.
w = 2.50 cm/s2; t = 2.00 s after the beginning of motion its position
corresponds to that shown in Fig. 1.7. Find:
(a) the velocities of the points A, B, and 0;
(b) the accelerations of these points.
1.54. A cylinder rolls without slipping over a horizontal plane.
The radius of the cylinder is equal to r. Find the curvature radii of
trajectories traced out by the points A and B (see Fig. 1.7).
1.55. Two solid bodies rotate about stationary mutually perpendicular intersecting axes with constant angular velocities col
3.0 rad/s and c0 2 = 4.0 rad/s. Find the angular velocity and angular acceleration of one body relative to the other.
1.56. A solid body rotates with angular velocity co = ati
bt2 j,
where a = 0.50 rad/s2, b = 0.060 rad/0, and i and j are the unit
vectors of the x and y axes. Find:
(a) the moduli of the angular velocity and the angular acceleration
at the moment t = 10.0 s;
(b) the angle between the vectors of the angular velocity and the
angular acceleration at that moment.
1.57. A round cone with half-angle a = 30° and the radius of the
base R = 5.0 cm rolls uniformly and without slipping over a horizontal plane as shown in Fig. 1.8. The cone apex is hinged at the
point 0 which is on the same level with the point C, the cone base
centre. The velocity of point C is v = 10.0 cm/s. Find the moduli of
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