Physics for Scientists and Engineers, Technology Update (No access codes included)
9th Edition
ISBN: 9781305116399
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 12, Problem 12.4CQ
To determine
The reason a person can’t bend forward without falling by putting their heels firmly against the wall.
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Chapter 12 Solutions
Physics for Scientists and Engineers, Technology Update (No access codes included)
Ch. 12 - Consider the object subject to the two forces of...Ch. 12 - Consider the object subject to the three forces in...Ch. 12 - A meterstick of uniform density is hung from a...Ch. 12 - For the three parts of this Quick Quiz, choose...Ch. 12 - The acceleration due to gravity becomes weaker by...Ch. 12 - A rod 7.0 in long is pivoted at a point 2.0 m from...Ch. 12 - Prob. 12.3OQCh. 12 - Two forces are acting on an object. Which of the...Ch. 12 - Prob. 12.5OQCh. 12 - A 20.0-kg horizontal plank 4.00 in long rests on...
Ch. 12 - Prob. 12.7OQCh. 12 - In analyzing the equilibrium of a flat, rigid...Ch. 12 - A certain wire, 3 m long, stretches by 1.2 mm when...Ch. 12 - The center of gravity of an ax is on the...Ch. 12 - A ladder stands on the ground, leaning against a...Ch. 12 - Prob. 12.2CQCh. 12 - (a) Give an example in which the net force acting...Ch. 12 - Prob. 12.4CQCh. 12 - Prob. 12.5CQCh. 12 - A girl has a large, docile dog she wishes to weigh...Ch. 12 - Prob. 12.7CQCh. 12 - What kind of deformation does a cube of Jell-O...Ch. 12 - What are the necessary conditions for equilibrium...Ch. 12 - Why is the following situation impossible? A...Ch. 12 - Prob. 12.3PCh. 12 - Prob. 12.4PCh. 12 - Your brother is opening a skateboard shop. He has...Ch. 12 - A circular pizza of radius R has a circular piece...Ch. 12 - Prob. 12.7PCh. 12 - Prob. 12.8PCh. 12 - Prob. 12.9PCh. 12 - Prob. 12.10PCh. 12 - A uniform beam of length 7.60 m and weight 4.50 ...Ch. 12 - A vaulter holds a 29.4-N pole in equilibrium by...Ch. 12 - A 15.0-in uniform ladder weighing 500 N rests...Ch. 12 - A uniform ladder of length L.and mass m1 rests...Ch. 12 - A flexible chain weighing 40.0 N hangs between two...Ch. 12 - A uniform beam of length L and mass m shown in...Ch. 12 - Figure P12.13 shows a claw hammer being used to...Ch. 12 - A 20.0-kg floodlight in a park is supported at the...Ch. 12 - Prob. 12.19PCh. 12 - Review. While Lost-a-Lot ponders his next move in...Ch. 12 - John is pushing his daughter Rachel in a...Ch. 12 - Prob. 12.22PCh. 12 - One end of a uniform 4.00-m-long rod of weight Fg...Ch. 12 - A 10.0-kg monkey climbs a uniform ladder with...Ch. 12 - A uniform plank of length 2.00 m and mass 30.0 kg...Ch. 12 - A steel wire of diameter 1 mm can support a...Ch. 12 - The deepest point in the ocean is in the Mariana...Ch. 12 - Assume Youngs modulus for bone is 1.50 1010 N/m2....Ch. 12 - A child slides across a floor in a pair of...Ch. 12 - Evaluate Youngs modulus for the material whose...Ch. 12 - Assume if the shear stress in steel exceeds about...Ch. 12 - When water freezes, it expands by about 9.00%....Ch. 12 - A 200-kg load is hung on a wire of length 4.00m,...Ch. 12 - A walkway suspended across a hotel lobby is...Ch. 12 - Review. A 2.00-m-long cylindrical steel wire with...Ch. 12 - Review. A 30.0-kg hammer, moving with speed 20.0...Ch. 12 - A bridge of length 50.0 m and mass 8.00 104 kg is...Ch. 12 - A uniform beam resting on two pivots has a length...Ch. 12 - Prob. 12.39APCh. 12 - The lintel of prestressed reinforced concrete in...Ch. 12 - Prob. 12.41APCh. 12 - When a person stands on tiptoe on one foot (a...Ch. 12 - A hungry bear weighing 700 N walks out on a beam...Ch. 12 - The following equations are obtained from a force...Ch. 12 - A uniform sign of weight Fg and width 2L hangs...Ch. 12 - A 1 200-N uniform boom at = 65 to the vertical is...Ch. 12 - Prob. 12.47APCh. 12 - Assume a person bends forward to lift a load with...Ch. 12 - A 10 000-N shark is supported by a rope attached...Ch. 12 - Why is the following situation impossible? A...Ch. 12 - A uniform beam of mass m is inclined at an angle ...Ch. 12 - Prob. 12.52APCh. 12 - When a circus performer performing on the rings...Ch. 12 - Figure P12.38 shows a light truss formed from...Ch. 12 - Prob. 12.55APCh. 12 - A stepladder of negligible weight is constructed...Ch. 12 - A stepladder of negligible weight is constructed...Ch. 12 - (a) Estimate the force with which a karate master...Ch. 12 - Two racquetballs, each having a mass of 170 g, are...Ch. 12 - Review. A wire of length L, Youngs modulus Y, and...Ch. 12 - Review. An aluminum wire is 0.850 m long and has a...Ch. 12 - Prob. 12.62APCh. 12 - A 500-N uniform rectangular sign 4.00 m wide and...Ch. 12 - A steel cable 3.00 cm2 in cross-sectional area has...Ch. 12 - A uniform pole is propped between the floor and...Ch. 12 - In the What If? section of Example 12.2, let d...Ch. 12 - Figure P12.67 shows a vertical force applied...Ch. 12 - A uniform rod of weight Fg and length L is...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- Stand with your heels and back against a wall and try to bend over and touch your toes. You’ll find that you have to stand away from the wall to do so without toppling over. Compare the minimum distance of your heels from the wall with the distance for a friend of the opposite sex. Who can touch their toes with their heels nearer to the wall: men or women? On the average and in proportion to height, which sex has the lower center of gravity?arrow_forwardAssuming your feet are not held down, which is more difficult: doing sit-ups with your knees bent or with your legs straight out?arrow_forwardA woman wearing a stiletto heel shoes (heel pointed shoes) gets tired and will feel pain in her legs easily. Why so?arrow_forward
- When you turn while running, you must lean in the direction of the turn or risk falling over. If you lean left as you turn left, why don’t you fall over to the left?arrow_forwardThe 3 m long uniform plank is supported by a fulcrum at the midpoint. Where should a 45 kg student must be from the midpoint to be able to balance the plank? 45 kg X = ? +0.4 m +0.5 m 30 kg 40 kgarrow_forwardThe bones of the forearm (radius and ulna) are hinged to the humerus at the elbow. The biceps muscle connects to the bones of the forearm about 2.15 cm beyond the joint. ,Biceps muscle Assume the forearm has a mass of 2.35 kg and a length of 0.445 m. When the humerus and the biceps are nearly vertical and the forearm is horizontal, if a person wishes to Humerus- hold an object of mass 5.75 kg so that her forearm remains motionless, what is the force exerted by the biceps muscle? Radius M Elbow- Ulna force: N Handarrow_forward
- Consider a ladder on a horizontal floor and leaning against a vertical wall. Which of the following is necessary for the ladder to be in equilibrium? both wall and floor must be rough the ladder can be in equilibrium even both floor and wall are perfectly smooth Rough floor Rough wallarrow_forwardThe bones of the forearm (radius and ulna) are hinged to the humerus at the elbow. The biceps muscle connects to the bones of the forearm about 2.15 cm beyond the joint. Assume the forearm has a mass 2.25 kg and a length of 0.425 m. When the humerus and the biceps are nearly vertical and the forearm is horizontal, if a person wishes to hold an object of mass 7.35 kg so that her forearm remains motionless, what is the force F exerted by the biceps muscle? Image is attached below. Please show all work.arrow_forwardTake a piece of modeling clay and put it on a table, then mash a cylinder down into it so that a ruler can balance on the round side of the cylinder while everything remains still. Put a penny 8 cm away from the pivot. Where would you need to put two pennies to balance? Three pennies?arrow_forward
- We have two masses balanced on a centered beam on a fulcrum. If m1 = 10 kg, and m2 = 20 kg, what should the length of the lever arm, r2, be to keep everything balanced when r1 = 10 meters?arrow_forwardThe bones of the forearm (radius and ulna) are hinged to the humerus at the elbow. The biceps muscle connects to the bones of the forearm about 2.15 cm beyond the joint. Assume the forearm has a mass of 2.35 kg and a length of 0.445 m.When the humerus and the biceps are nearly vertical and the forearm is horizontal, if a person wishes to hold an object of mass 4.95 kg so that her forearm remains motionless, what is the force exerted by the biceps muscle?arrow_forwardAs a part of his daily workout routine, he lifts 10-kg dumbbells on each hand. His hands and forearms weigh 4 kg each. If the length of each of his forearms and hands are 0.5 m, determine the force exerted by his muscles? Assume that the center of gravity of the forrearms are in the middle.arrow_forward
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