
192 Forensic Engineering Fundamentals
e analysis used to compute the forces in Table 7.1 follows:
A free body diagram of the forces involved if the load is pulled horizontally F
h
, and the
ramp are shown in Figure 7.2.
Summing forces
y
h
=→=
(7.1)
(7.2)
FW
i
µ
(cos si
(7.3)
Load
A
i
F
h
Figure 7.2 Dolly on a ramp.
Table 7.1 Force Required to Pull a Dolly and Load
Up a Ramp
A
i
μ
s
= 0.05 μ
s
= 0.10 μ
s
= 0.15
F
h
F F
h
F F
h
F
0 12.82 17.27 25.65 32.96 38.47 47.30
2 21.76 29.30 34.58 44.44 47.39 58.26
4 30.67 41.30 43.57 55.86 56.26 69.16
6 39.55 53.25 52.30 67.22 65.05 79.98
8 48.37 65.53 61.07