Multiple Choice
Passage
Laparoscopy is a minimally invasive surgical procedure where small surgical instruments are inserted into the body through cannulas (hollow tubes 0.5 to 1.0 cm in diameter) . A cannula is inserted into the skin while sleeved around a trocar (Figure 1) . The skin incision can be made directly with a sharp-tipped trocar as it is being inserted with the cannula. If a blunt-tipped trocar is used, the incision is made beforehand with a surgical blade. After insertion, the trocar is removed, leaving the cannula as an access point for laparoscopic procedures.
Figure 1 Cannula, trocar, and two types of tipsLow-friction trocars increase surgical precision and reduce postoperative scarring. Friction between the skin and trocar tip is tested with synthetic skin and a stationary ramp whose surface is made of the same material as the trocar. For testing, the synthetic skin is pressed against the ramp's surface by a load, weighted to allow the skin to slide down at a constant speed (Figure 2) . In this setup, the weight of the synthetic skin layer is negligible.
Figure 2 Experimental setup to test the friction between trocar and skin
Adapted from W. Firme-Gustavo et al., (C) 2015 Society of Laparoendoscopic Surgeons.
-When the angle of inclination of the ramp increases, kinetic friction:
A) decreases because the weight component perpendicular to the ramp decreases.
B) decreases because the weight component parallel to the ramp decreases.
C) increases because the weight component perpendicular to the ramp increases.
D) increases because the weight component parallel to the ramp increases.
Correct Answer:

Verified
Correct Answer:
Verified
Q69: A marble rolls down a slope at
Q70: Passage<br>In hemodynamics, blood flow through the cardiovascular
Q71: Passage<br>For a person with perfect vision, light
Q72: Passage<br>Ultrasound is a technique that uses the
Q73: Passage<br>In mass spectrometry, a sample's molecules are
Q75: Passage<br>A traumatic brain injury (TBI) is a
Q76: Passage<br>In hemodynamics, blood flow through the cardiovascular
Q77: Passage<br>Positron emission tomography (PET) is a medical
Q78: An ideal fluid flows through a tube
Q79: Passage<br>Nitrogen is extremely cold in its liquid