Answer:
27.1 m/s
Explanation:
Given that at a race car driving event, a staff member notices that the skid marks left by the race car are 9.06 m long. The very experienced staff member knows that the deceleration of a car when skidding is -40.52 m/s2.
Using third equation of motion,
V^2 = U^2 + 2aS
Since the car is decelerating, the final velocity V = 0
Substitute all the parameter into the equation above,
0 = U^2 - 2 * 40.52 * 9.06
U^2 = 734.22
U = 
U = 27.096
U = 27.1 m/s approximately
Therefore, the staff member can estimate for the original speed of the race car to be 27.1 m/s if it came to a stop during the skid
5.4 x 1014Hz
wavelength x frequency = the speed of light
Answer:
Cat and a dog
Explanation:
The cat might bark instead of meow because it has certain traits from the dog. The dog however may still bark because it is a dog!
Answer: She is incorrect to conclude that the reaction is endothermic.
As in the second trial, the temperature has increased by 20 °C , that means the heat has been released and energy is released in exothermic reactions.
Exothermic reactions: The reactions in which the energy of the products is less than the energy of the reactants, and the excess energy is released as heat.
Endothermic reactions: The reactions in which the energy of the products is more than the energy of the reactants, and the excess energy is absorbed as heat.
We know that a=vf_vi/t equals equation "a" . Where a is the acceleration of the body , vf is the final velocity , vi is the initial velocity and t is equal to time . Since vi equals o m/s , vf equals to 60 m/s and t equals 10 s. Put in equation "a". a=60-0/10 =6m/s2
