# Search results

1. ### Young's modulus of spider thread

Homework Statement Q 1. A spider with a mass of 0.26 g hangs vertically by one of its threads. The thread has a Young’s modulus of 4.7 x 10^9 N/m2 and a radius of 9.8 x 10^- ^6 m. a) What is the fractional increase in the thread’s length caused by the spider? b) Suppose a 76 kg person...
2. ### Rotational motion

On his last throw of the Atlanta Olympics, Lance Deal launched the hammer 81.12m, good enough for a silver medal. The hammer is thrown by rotating the body in a circle, building up rotational speed until releasing it and letting the rotational velocity change to translational velocity. The...
3. ### Rotational motion of bicep

would someone be able to tell me if this is right or what i've done wrong? thankyou Homework Statement a) What torque does the bicep muscle have to apply to hold the forearm of mass 1.10 kg and length 30 cm horizontally? Assume the arm is a rod of uniform mass density. b) What torque does...
4. ### Electricity prob

The values for the resistors are: R1=7\Omega, R2=5\Omega, R3=4\Omega (see diagram for placement of the resistors) 1) Suppose there is a current of 0.6A going through R1 and that the voltage supplied by the battery is 9V, determine the value of R4 2) Using the information above, determine the...
5. ### Pressure of fluid on bottom of container

A cylindrical container with a cross sectional area of 65.2 cm^{2} holds a fluid of density 806kg/m^{3}. At the bottom of the container the pressure is 116 kPa a) What is the depth of the fluid? b) Find the pressure at the bottom of the container after an additional 2.05 \times 10^{-3} m^{3}...
6. ### Pressure of fluid in container

Homework Statement A cylindrical container with a cross sectional area of 65.2 cm^{2} holds a fluid of density 806kg/m^{3}. At the bottom of the container the pressure is 116 kPa a) What is the depth of the fluid? b) Find the pressure at the bottom of the container after an additional 2.05...
7. ### Another motion prob

_{}Homework Statement If a long jumper at the top of his projectory is moving at 6.5 m/s (horizontally) and his cantre of mass is 1.1m above where it was when he launched into the jump, how fast must he have been moving when he launched? Homework Equations v_{x} = v_{0x} + a_{x}t x =...
8. ### Density prob

Homework Statement a person sits in a harness hamging in mid-air from a set of scales. the scales display her weight as 550.0 N. she then empties her lungs as much as possible and is completely immersed in water. the scales now give her weight as 21.2 N. what is her average density...
9. ### Motion equations problem

I have a problem from a practice physics exam: The specifications for design of a playgroud slide say that a child should gain a speed of no more than 15m/s by sliding down the eqipment. How tall can the slide be? these are the equations that we'll be given in our exam: v_{x} = v_{0x} +...