Physics Answers

I rode my bicycle to my grandmother's house at 6 km/hr on a flat road for 5 minutes before reaching a hill. I went at 2 km/hr up the hill for 3 minutes. I met a friend and stopped to talk for 5 minutes . I went on at 2 km/hr to my grandmother's house. draw ( plot ) the velocity against the time graph for this motion

A person is jumping from a height h0 = 10 m with zero initial velocity and a cricket ball is thrown directly upward with an initial velocity v0 = 9.8 m/s at the same instant when time t = 0 s as shown in Fig. 1. Consider h = 11.5 m and i and j to be the unit vectors along the X and Y axis. Gravity is acting along the j direction and the magnitude of gravitational acceleration is given by g = 9.81 m/s2 . The red dot on the person represents his center of mass

(c) Now consider when the person hits the ground, he bends his knees such that the center of mass of his body is lowered by 15 cm. If the maximum force that the bone of his legs can withstand is 50000 N, will he break his legs?

A person is jumping from a height h0 = 10 m with zero initial velocity and a cricket ball is thrown directly upward with an initial velocity v0 = 9.8 m/s at the same instant when time t = 0 s as shown in Fig. 1. Consider h = 11.5 m and i and j to be the unit vectors along the X and Y axis. Gravity is acting along the j direction and the magnitude of gravitational acceleration is given by g = 9.81 m/s2 . The red dot on the person represents his center of mass.

(b) If it takes 0.01 seconds for the person to come to complete rest when he hits the ground, calculate the average force acting on the person

A person is jumping from a height h0 = 10 m with zero initial velocity and a cricket ball is thrown directly upward with an initial velocity v0 = 9.8 m/s at the same instant when time t = 0 s as shown in Fig. 1. Consider h = 11.5 m and i and j to be the unit vectors along the X and Y axis. Gravity is acting along the j direction and the magnitude of gravitational acceleration is given by g = 9.81 m/s2 . The red dot on the person represents his center of mass. (a) if the person and the cricket ball consist of a system, find the position and velocity of the center of mass of the system at time t = 0.5 s. (b) If it takes 0.01 seconds for the person to come to complete rest when he hits the ground, calculate the average force acting on the person. (c) Now consider when the person hits the ground, he bends his knees such that the center of mass of his body is lowered by 15 cm. If the maximum force that the bone of his legs can withstand is 50000 N, will he break his legs?

Consider an automobile moving at v mph that skids d feet after its brakes lock. Calculate how far it would skid if it was moving at 2v and the brakes were locked.   

How pure metals and a semi conductor can be distinguished through the effect of temperature on their electrical resistance

What is the angular velocity of an object traveling in a circle of radius 0.75 with a linear speed of 3.5m/s?

A shopper pushes a grocery cart for a distance 19 M at a constant speed on level ground, against a 25 N frictional force. He pushes in a direction 25.5 degrees below the horizontal.

​1 kg block vibrates in shm with amplitude of 15 cm and period of T = 2 s find the frequency, its maximum speed and its speed

when the displacement is 5cm, its maximum acceleration when the displacement is 5cm.

determine the force of gravitational attraction between the earth 5.98 x 10^24 kg and a 70 kg boy who is standing at sea level, a distance of 6.38 x 10^4 in from earth's center.