Help with 2 questions You stand on a scale and then push off to jump. The scale reads 112 kg when the acceleration of your centerof mass during is 17 m/s?. What did the scale read when you stood stationary on the scale? Answer in kg.Note your center of mass is accelerating upwards but your feet are still contact with the scale.Don't guess. Use the free body diagram method.Use g=10 m/s² if you need g. A box is pushed up the ramp by the horizontal force shown. The mass of the box is M and the pushing force isFo. The coefficient of kinetic friction is 0.3 and that of static friction is 0.5.How large is the kinetic friction force?Don't guess. Draw the free body diagram and use the free body diagram method.F,+yO 0.3 Mg sin(0)O 0.3 ( Mg cos(e) + F, sin(e) )O 0.3 F, sin(0)0.3 F.0.3 (Mg cos(0) - Fo sin(0) )0.3 Mg cos(0)0.3 Mg

Answer to the second question is

A box is pushed up the ramp by the horizontal force shown. The mass of the box is M and the pushing force is Fo. The coefficient of kinetic friction is 0.3 and that of static friction is 0.5. How large is the kinetic friction force? Don't guess. Draw the free body diagram and use the free body diagram method.

A box is pushed up the ramp by the horizontal force shown. The mass of the box is M and the pushing force is Fo. The coefficient of kinetic friction is 0.3 and that of static friction is 0.5. How large is the kinetic friction force? Don't guess. Draw the free body diagram and use the free body diagram method.

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter6: Momentum And Collisions

Section: Chapter Questions

Problem 25P: An astronaut in her space suit has a total mass of 87.0 kg, including suit and oxygen tank. Her...

See similar textbooks

Similar questions

In Chapter 9, we will define the center of mass of an object and prove that its motion is described by the particle under constant acceleration model when constant forces act on the object. A gymnast jumps straight up, with her center of mass moving at 2.80 m/s as she leaves the ground. How high above this point is her center of mass (a) 0.100 s, (b) 0.200 s, (c) 0.300 s. and (d) 0.500 s thereafter?
An astronaut in her space suit has a total mass of 87.0 kg, including suit and oxygen tank. Her tether line loses its attachment to her spacecraft while shes on a spacewalk. Initially at rest with respect to her spacecraft, she throws her 12.0-kg oxygen tank away from her spacecraft with a speed of 8.00 m/s to propel herself back toward it (Fig. P6.29). (a) Determine the maximum distance she can be from the craft and still return within 2.00 min (the amount of time the air in her helmet remains breathable), (b) Explain in terms of Newtons laws of motion why this strategy works. Figure P6.29
In a soccer match against Mexico in 2014, US Women’s National Team striker Alex Morgan scored a sweetheaded goal in the 79th minute of the game. Just as the ball left her head, the horizontal component of its acceleration was 225 m/s , and the vertical component of its acceleration was -200 m/s (assuming thepositive direction points up). If the ball has a mass of 425 g, what was the magnitude and direction of theforce she applied to the ball? Note- you can ignore the weight of the ball.
A 1Zero Suit Samuskg object is located at a distance of 6.4 x106 m from the center of a larger object whose mass is 6.0 x 1024 kg. What is the size of the force acting on the smaller object?
Sharon pushes a tall box across the floor. Her arms (and therefore her push force) of F = 400 N make a theta= 30 degree angle with the horizontal. Since the box rests on ball bearings it is essentially frictionless. Sick of her job, Sharon decides to give the box a brief shove lasting only t = 0.2 seconds. Find the velocity (magnitude and direction) of the box at the completion of Sharon's shove, assuming (a) the box's weight is 490 N, and (b) the box's weight is 122.5 N. In both cases, the box starts from rest.
Brian stands on one foot, and then lifts his heel off the floor by flexing his calf muscles. His Achilles' tendon connects the gastrocnemius and soleus (calf) muscles at a 75-degree angle to the calcaneus (heel), five cm from the axis, where his tibia (shin) joins with the callus (ankle). His metatarsals (toes) end fifteen em from this axis, with foot tilted 40-degrees from the ground. a.) Brian's mass m = 50kg is all held up by a normal force applied at his toes. How much torque does this force apply about the axis of his ankle? b.) What is the magnitude of the force Brians calf is exerting on his heel? Hint: Torques... about Ankle axis... c.) What are the magnitude and direction of the force that Brians tibia is applying to the ankle?
During a visit to the International Space Station, an astronaut was positioned motionless in the center of the station, out of reach of any solid object on which he could exert a force. Suggest a method by which he could move himself away from this position, and explain the physics involved.
What average force is required to stop a 1400 kg car in 8.0 s if the car is traveling at 85 km/h? Express your answer to two significant figures and include the appropriate units. Enter positive value if the direction of the force is in the direction of the initial velocity and negative value if the direction of the force is in the direction opposite of the initial velocity.
• At the local grocery store, you push a 14.5-kg shopping cart. Youstop for a moment to add a bag of dog food to your cart. With aforce of 12.0 N, you now accelerate the cart from rest through adistance of 2.29 m in 3.00 s. What was the mass of the dog food?
Your forehead can withstand a force of about 6.0 kN before fracturing, while your cheekbone can withstand only about 1.3 kN. Suppose a 140 g baseball traveling at 40 m/s strikes your head at an angle of 20 degrees from the horizontal. The forehead can undergo a displacement of roughly about 0.75mm before a fracture and the cheekbone only about 0.2mm. What is the magnitude of the force that stops the baseball? What force does the baseball exert on your head? Explain. Are you in danger of a fracture if the ball hits you in the forehead? On the cheek? What is the time interval necessary for either the forehead or cheek bone to break based on the forces stated?
Two blocks of mass ? and 2? rest on a rough incline plane with coefficient of kineticfriction ??. The two blocks are connected to a cable with tension ?1, and the block of mass ? isconnected to a ball of mass ? by a cord over a lightweight, frictionless pulley with tension ?2, asshown below. When the system is released from rest, the ball of mass ? accelerates downward,and the two blocks accelerate up the incline. You may ignore the mass of each cord.
While skydiving, a brilliant young physics student known affectionately as “Crazy Kaitlin”launches herself horizontally out of an airplane. The plane is flying steadily at 12,500 feetabove the Earth with a horizontal speed of 80 miles per hour. The total mass of Kaitlinand her gear is 75-kg. Assume g = -9.8 m/s2 While free-falling, Kaitlin engages in some aerial acrobatics. At one point, she finds herself rapidly spinning aboutan axis that runs from her head to her feet. If she wants to quickly decrease her rate of spin, the optimum way forher to this is:A) Cup her hands and claw wildly at the air B) Use counter-flagellation forcesC) Fold her arms tightly across her chest to decrease her moment of Inertia.D) Stretch her arms and legs as far outward as possible to increase her moment of Inertia