What is the reaction force when baseball catcher catches and stops a baseball?

Aforce of 240.0 n causes an object to accelerate at 3.2 m/s2. what is the mass of the object?

One day, after pulling down your window shade, you notice that sunlight is passing through a pinhole in the shade and making a small patch of light on the far wall. you see that the patch of light seems to be a circular diffraction pattern. it appears that the central maximum is about 1 cm across and you estimate that the distance from the window shade to the wall is about 3 m. what is (a) the average wavelength of sunlight? (b) the diameter of the pinhole?

What is a good example of instantaneous speed