Homework Statement
A person holds a 12.0-kg dumbbell in his hand with his forearm in the horizontal position as shown in Figure 1. The biceps muscle is attached a distance d=4.0 cm from the joint and the dumbbell is a distance l=45 cm from the joint. This system is in static equilibrium. It is...
Homework Statement
A 0.570-{\rm kg} wood block is firmly attached to a very light horizontal spring(k=180 N/m). It is noted that the block-spring system, when compressed 4.4 cm and released, stretches out 1.7 cm beyond the equilibrium position before stopping and turning back.
What is the...
Homework Statement
What minimum horsepower must a motor have to be able to drag a 270 kg box along a level floor at a speed of 1.20 m/s if the coefficient of friction is 0.50?
Homework Equations
Ffr=mu*mg
W=Ffr*d
The Attempt at a Solution
I ended up having W=Fr*d=mu*m*g*d...
Suppose that a binary-star system consists of two stars of equal mass. They are observed to be separated by 350 million {\rm km} and take 5.4 Earth years to orbit about a point midway between them.
I got 1.1x10^29 as my answer, but it is incorrect. Can anyone help me out?
A jet pilot takes his aircraft in a vertical loop
a. If the jet is moving at a speed of 1300 km/h at the lowest point of the loop, determine the minimum radius of the circle so that the centripetal acceleration at the lowest point does not exceed 6.7 g's.
b. Calculate the 75-{\rm kg}...