As shown in the figure below, there is a 5-kg block being pulled across a surface at a constant speed by a rope attached at a 25˚ angle above the horizontal. The tension in the rope is 20 N.

Which seasons are the northern and southern hemispheres experiencing in the image? it is summer in both the northern and southern hemispheres. it is summer in the northern hemisphere and winter in the southern hemisphere. it is winter in both the northern and southern hemispheres. it is winter in the northern hemisphere and summer in the southern hemisphere.

Arod of some material 0.20 m long elongates 0.20 mm on heating from 21 to 120°c. determine the value of the linear coefficient of thermal expansion [in (degrees c)^-1] for this material.

There are two-speed cameras, one in an are where the speed limit is 30 km/h and another where the speed limit is 50 km/h. in which will there be a smaller time interval between the photographs? explain your answer.