Acar in dynamic equilibrium is acted upon by the following forces:
force due to gravity= -9000 newtons
force due to friction = -250 newtons
forward force exerted by engine = 250 newtons.
what is the value of the force exerted by the ground on the car?

We want to calculate the total metabolic heat generated by a singing canary taking into account heat transfer by radiation, convection and exhaling air. the air temperature is 20 oc, canary’s body internal and surface temperature is 33oc, external body surface convective heat transfer coefficient is 25.2 w/m2 .k, temperature difference between the inhaled and exhaled air is 4.3 oc, the ventilation rate is 0.74 cc of air per second, specific heat of air is 1.0066 kj/kg.k and density of air is 1.16 kg/m3 . assume the canary’s body to be a cylinder with 7 cm diameter and 9 cm length, and heat exchange is from the side as well as the top and bottom of cylinder. calculate 1) the net rate of heat lost by radiation, assuming heat gained by the bird through radiation from the surroundings is 11.5 w; 2) rate of heat transferred by convection to the surrounding air; 3) rate of heat transferred in the exhaling air without considering any internal evaporation; 4) total metabolic power.

Jessie ran 5000 meters from the cops and an average speed of 6 meters / second before he got caught . how long did he run?

What do you think car designers do if the damage caused by a crash test is too severe?