Answer:
6.2 seconds
Explanation:
Using Newton's second law, ∑F=ma, we know the net force acting on the object is Force applied-Force of friction. The net force is 203 N. Newton's second law requires the mass of an object, not the weight force, so we will have to calculate the mass. We know that m*g=weight force, in this case, solve for the mass and you will get 210 kg. Now that we have the value of the net force and the mass, we can solve for acceleration. =0.967 m/s^2. Now, since we have the acceleration, initial velocity(0 m/s), and the final velocity (6m/s) we will use these to solve for time using the kinematic equation Vf=Vi + at. Plug in the values we know and solve for time and you will get 6.2 seconds
I think the answer is D. permit the wave to travel through it
An increase in the level of nitrogen dioxide and a decrease in the level of ground-level ozone occurs.
Explanation:
Ozone gas is normally found in stratosphere, it protects us from solar radiation. Under certain circumstances, it can be formed on the ground level.
Conditions that have to be met in order for this to happen are existing of nitrogen oxides and volatile organic compounds and their reaction catalyzed by heat and light.
During dark, cold and cloudy days, due to the lack of heat and light from the Sun, formation of ozone will be decreased.
Also, this will enable building up of nitrogen dioxide, due to the same reason, leading to increased concentration.
the force of effort is given as
E = effort force = 280 N
m = mass of box to be lifted = 320 kg
g = acceleration due to gravity = 9.8 m/s²
force of load due to weight of box is given as
L = force of load = mg
L = 320 x 9.8
L = 3136 N
mechanical advantage for pulley system is the simply the ratio of the effort put in to the load being lifted.
mechanical advantage is given as
MA = load/effort
MA = L/E
MA = 3136/280
MA = 11.2