Recent content by 9giddjl

Hello! I have a question: Why is it easier to do sit-ups with your hands on your stomach, than with your hands behind your head? Our teacher told us that it is easier because the moment arm is closer to the axis of rotation.. but I still don't fully understand..because I also read in my...

ok that makes sense! I think I understand now...Thankyou so much! many many thanks:)

sorry! I thought i knew how to use the rule.. for example.. if i wrap my finger around a wire i point my thumb in the direction of the current and then my fingers represent the direction of the magnetic field? But I don't think I understand it really... could you please explain it to me?

Homework Statement Consider Figure 25.14 (attached photo). In the figure, two separate wires are in close proximity. If wire A carries a current of 1.5 A and wire B carries a current of 2.5 A, calculate the value of the magnetic field strength at a point x between the two wires. Homework...

Homework Statement Monochromatic light of 585 nm is shone on a slit of width 8.0 x 10^-2 mm and the interference pattern is produced on a screen 1.8 m from the source. What is the width of the first-order bright fringe? Homework Equations PD/w=x/L The Attempt at a Solution...

Homework Statement At a certain temperature a sample of oxygen has a pressure of 2.0 x 10^6 Pa, and a density of 4.0 x 10^-3 g cm^-3. Find the average speed of the oxygen molecules of the gas. Homework Equations Ek= 3/2kT Ek= 1/2mv^2 The Attempt at a Solution I know that the mass...

thankyou very much:) that makes sense:)

Homework Statement A diver dives to a depth of 40 m in fresh water where he releases a toy balloon of volume 10 cm^3. What will be the size of the balloon when it reaches the surface? (The pressure increass at a rate of 1 atmosphere for every 10 m descent in fresh water) Homework...

i used 1/2 ML^2 for the moment of inertia and it yielded the correct answer! thankyou for ur help wise teacher!:)

Homework Statement Consider a simple helicopter blade, attached to a bolt at its end. The bolt is made to rotate by a powerful motor, and the blade therefore rotates. The blade has a length L= 7.8 m and mass M= 100 kg. The blade is shaped approximately like a long thin, uniform rod. What...

Angular Speed of Earth when... Homework Statement Determine the angular speed with which the Earth would have to rotate on its axis so that a person on the equator would weigh 75% of their present weight (Radius of the Earth is 6400 km) Homework Equations wf=2pi/T wt= mg v=wr...

Thank you. I understand how to do the question now. The answer is +15/8 Q.

Electrostatics question, need help urgent! Homework Statement A small metal sphere carrying a charge of -2Q is first brought into contact with sphere R Which has a charge of +Q, and then into contact with sphere S which has a charge of +2Q, and finally into contact with sphere T which has a...

i get it now! Thankyou soo much! Kind regards:)

Homework Statement An ice tray containing 200 g of water at 25 degrees celecius is placed in the freezer. How much heat energy has to be removed to change the water into ice at -4 degrees celsius? Homework Equations Q= mc(Tf-Ti) + MLf + mc(Tf-Ti) The Attempt at a Solution I know...