Chiếu một tia tới SI lên gương phẳng nằm ngang. Nếu giữ nguyên tia này rồi quay gương đi một góc a quanh trục O nằm trong mặt gương và vuông góc với mặt phẳng tới thì tia phản xạ quay một góc bằng bao nhiêu? Xét hai trường hợp : a) Trục O đi qua điểm tới I
b) Trục O không đi qua điểm tới I

10 is the . . .

Question 1 answer: make sure you eat healthy foods and excercise atleast once a day.question 2 answer: sometimes bullying . bullying lowers a persons self-esteem sometimes which can make them not care for themselves to much making them feel bad about there body structer. that or they just have a bad body structer and there family/doctor said its unhealthy how they eat.

To compare speeds speeds of wagons we will use second newton's law. it states: f = m * ahere we can see that force depends on the acceleration. if we know acceleration for both wagons we can compare them to make conclusion of speeds of wagons.we have: m1 = 10lbm2 = 20lbf1 = 2*f2also: m2 = 2*m1for bill we have equation: f1 = m1 * a1for tom we have equation: f2 = m2 * a2after inserting identities we have: 2*f2 =m1 * a1f2 = 2*m1 * a2in order to make conclusions about speeds we will solve these equations for a and find their ratio: a1 = 2f2 / m1a2 = f2 / 2m1a1 / a2 = (2f2/m1) / (f2/2m1)a1 / a2 = (2f2*2m1) / (m1*f2)a1 / a2 = (4f2m1) / (m1f2)a1 / a2 = 4this ratio is bigger than 1 and this means that a1 is greater than a2. a1 is 4 times greater than a2. speed of bill's wagon is 4 times greater than speed of tom's wagon.