Deck 11: Circular Motion, Component, and Structures

Question 1

Decide whether each of these statements is True (T) or False
For an object rotating with a constant speed in a circular path:
(i) The velocity is constant.
(ii) The acceleration is zero.

A) (i) T (ii) T
B) (i) T (ii) F
C) (i) F (ii) T
D) (i) F (ii) F

Answer 1

D

Question 2

Decide whether each of these statements is True (T) or False
For an object of constant mass rotating with a constant speed in a circular path, the centripetal force is
Increased if:
(i) The radius of the path is increased.
(ii) The speed of rotation is increased.

A) (i) T (ii) T
B) (i) T (ii) F
C) (i) F (ii) T
D) (i) F (ii) F

Answer 2

A

Question 3

Decide whether each of these statements is True (T) or False
For a vehicle rounding a horizontal corner, if there is to be no reliance on frictional forces and no skidding,
The angle of the banking has to be increased if:
(i) The radius of the corner is increased.
(ii) The vehicle speed is increased.

A) (i) T (ii) T
B) (i) T (ii) F
C) (i) F (ii) T
D) (i) F (ii) F

Answer 3

C

Question 4

An object of mass 1 kg is whirled round in a horizontal circle of radius 0.5 m on the end of a rope. When it rotates at 4 rev/s, the tension in the rope is:

A) 8 N
B) 158 N
C) 316 N
D) 632 N

Question 5

Decide whether each of these statements is True (T) or False
A reinforced short concrete column consists of axially placed steel reinforcing rods rigidly held in the
Concrete matrix.
(i) The stress on the rods and the concrete will be the same.
(ii) The strain on the rods and the concrete will be the same.

A) (i) T (ii) T
B) (i) T (ii) F
C) (i) F (ii) T
D) (i) F (ii) F

Question 6

The force required to shear a lap joint made using a single 20 mm diameter rivet, if the shear strength is 250 MPa, is:

A) 78.5 kN
B) 157 kN
C) 314 kN
D) 796 kN

Question 7

Decide whether each of these statements is True (T) or False
At a point of contraflexure for a beam:
(i) The bending moment is zero.
(ii) The bending moment changes from being positive on one side to negative on the other.

A) (i) T (ii) T
B) (i) T (ii) F
C) (i) F (ii) T
D) (i) F (ii) F

Question 8

Decide whether each of these statements is True (T) or False
When three concurrent forces are in equilibrium:
(i) Their vertical components must be zero and their horizontal components must also be zero.
(ii) If we determine the resultant of two of the forces it must be in the same direction and size as the third
Force.

A) (i) T (ii) T
B) (i) T (ii) F
C) (i) F (ii) T
D) (i) F (ii) F