Category: Physics

What happens when tryptophan is present? When tryptophan is present in the cell, two tryptophan molecules bind to the trp repressor, which changes shape to bind to the trp operator. Binding of the tryptophan–repressor complex at the operator physically prevents the RNA polymerase from binding and transcribing the downstream genes. What time should I take […]

What do water ice and steam have in common? When water freezes, its molecules move farther apart, making ice less dense than water. This means that ice will be lighter than the same volume of water, and so ice will float in water. As some of the water vapor cools, we see it as a […]

What are the five characteristics of fungi? Characteristics of Fungi Fungi are eukaryotic organisms means they have true nucleus which are enclosed in membranes. They are non-vascular organisms. Fungi have cell walls (plants also have cell walls, but animals have no cell walls). There is no embryonic stage for fungi. They reproduce by means of […]

How does the nucleus change in beta decay? A beta results in a neutron emitting a high energy electron and becoming a positive proton. Beta decay changes the atomic number of the nucleus by increasing the number of protons, by decreasing the number of neutrons while leaving the atomic mass essentially the same. What does […]

Does an object have no energy moving? Kinetic and potential energies are found in all objects. If an object is moving, it is said to have kinetic energy (KE). Potential energy (PE) is energy that is “stored” because of the position and/or arrangement of the object. And in falling, can exert forces and do work […]

What are 3 features of karst topography? Karst, terrain usually characterized by barren, rocky ground, caves, sinkholes, underground rivers, and the absence of surface streams and lakes. It results from the excavating effects of underground water on massive soluble limestone. What are karst landscapes used for? Karst environments in New South Wales were among the […]

What is the acceleration of a falling skydiver? Near the surface of the Earth, any object falling freely will have an acceleration of about 10 m/s 2. What happens to a skydivers acceleration? The skydiver accelerates towards the ground. As the skydiver gains speed, their weight stays the same but the air resistance increases. There […]

How will chemistry help us in the future? Research is constantly deepening our understanding of chemistry, and leading to new discoveries. Chemistry will help us solve many future problems, including sustainable energy and food production, managing our environment, providing safe drinking water and promoting human and environmental health. What is the role of chemistry in […]

Can coefficient of drag be negative? Drag coefficient cannot be negative in steady flow and a negative value of drag coefficient in steady flow indicates a computational error. It can however be zero in unsteady flow instantaneously. Negative drag is thrust. Why is drag negative? When drag is termed “positive”, that means that it is […]

What is Stonehenge aligned with? The sarsen stones, put up in at the centre of the site in about 2500 BC, were carefully aligned to line up with the movements of the sun. If you were to stand in the middle of the stone circle on midsummer’s day, the sun rises just to the left […]