block with string

A 3.62 kg block located on a horizontal floor is pulled by a cord that exerts a force F = 10.6 N at an angle theta = 34.0° above the horizontal, as shown in the figure. The coefficient of kinetic friction between the block and the floor is 0.09. What is the speed of the block 3.1 s after it starts moving?

True or false questions regarding the acceleration of an elevator.

An object of mass m is hanging by a string from the roof of an elevator. We want to compare the tension in the string to the weight of the object under various conditions. Which statements are true? (Give ALL correct answers) A) If the elevator is moving upwards, but slowing down, the tension in the string is equal to the object's weight B) If the elevator is moving downwards in free fall, the tension in the string is equal to the object's weight C) If the elevator is moving downwards, and speeding up, the tension in the string is less than the object's weight D) If the elevator is moving upwards, and speeding up, the tension in the string is less then the object's weight ... click for more

Calculating the coefficient of friction in centripetal movement.

A car goes around a flat curve with a radius of 65m at a speed of 49 km/hr. What must be the minimum coefficient of friction between the tires and road for the car to make the turn without skidding?

string and stone

A stone of mass 6.00 kg is attached to a strong string and whirled in a vertical circle of radius 44 cm. At the exact top of the path, the tension in the string is 4.2 times the stone's weight. What is the speed of the stone at this position (top of its path)?

Planet Deneb

We call the acceleration due to gravity on the Earth's surface "g". The planet Deneb Prime has a mass of 280 times that of Earth and a radius of 6 times that of Earth. Compared to Earth, what is the acceleration due to gravity on Deneb Prime? Express your answer in g's. So if you compute a value for the gravitational acceleration on Deneb Prime of, for example, 3.2g, you should simply enter "3.2" - without the quotation marks, of course